Unless otherwise noted, this series is rated PGish, depending on your definition of cuddles being PG or PG-13.
As always, I don't own, hold a claim to, or mean to infringe on any copyrights, nor do I make a claim about the actors, just the characters they play so well that inspired my muse (or the Writing Demon's as they're known). I don't know all the people that have a claim and they would be too numerous to mention so I'll leave that part out, putting in a simple, "not mine, don't sue me, I'm a poor college student and didn't mean any harm".
Okay, four things:
a) this starts out as a Derek/Philip, Willow/Oz, Buffy/Nick series, but all bets are off as to who ends up in who's bed when it'sall said and done.
b) my muse wanted angst so there's tons of it and it's mostly Xander based.
c) this is mostly 'ship stuff, especially since a good third of the stories are rated PG
d) there are slight crossovers in here, of a take a character from a fandom and run to this series sort. They include, but may not be limited to by the time the series is done, Forever Knight (Nick), due South (Ray K.), and Highlander (Methos and guest-appearances mostly).
Now that you've been warned, onto the Fics:
1. Changing Times: How it all began and the two groups came together.
2. Changing Habits: Rupert comes back, Buffy goes hunting, Xander hears some news, and they have Christmas
3. Life Changes: (ANGST!) Willow gets curious about presents and everybody else hears about what Nick and Xander know.
4. Resolutions: (ANGST!) They bring Xander back home and work it out.
5. Metamorphosis: Philip has to leave for a while, Xander and Oz get closer after he finds out what the guy's really been doing.
6. Duality: Oz figures Xander out more and they meet some aliens.
7. Truth Revealed: Xander lets his predator out to play, gets his perfect car, and the Scooby Gang talks about stuff. They meet an old friend of the House's and an old enemy too.
8. Young Again: most of the house is young again and the rest have to deal with their own problems.
9. Inner Truths: they find the reason for the youth, Oz searches out Xander to understand better, and Xander's inner predator comes out to play in the house.
10. Outer Truths: Things get fixed.
11. Changing Again: Ah, blissful quarantine - or not. The aliens are back.
12. Cures and Friendships: It's cured and Willow enlightens the guys to what they really want.
13. Stupidity Rules!: Giles end up married and the house has to deal with it.
14. Oh, Yeah, Not a Good.: Let's see - Willow gives birth, Xander gets a head injury.
Journal Series: Personal Diary, Willow Rosenberg: (Set night before the birth)
15. New Ideas and Reasons: (NC-17): Xander's found and some good things happen when Derek finds out whyit all happens.
16. Changelings and Traumas: A misunderstanding, some DNA, and a hostage situation. Pretty full story.
17. Protective Instincts: (Incidence and discussion of child abuse. so could be rated R): Xander finds the kids being hurt so he does something about it. A gossip problem too. Oh, and Buffy gets to drive Nick's Mustang!
18. New Things: (NC-17): A new nanny, an introduction into the non-traditional community, and we find some stuff out about the babies. A wolfy problem with a problematic member and the guys work out dominance issues between them.
Journal Series: Private Journal of Derek Rayne: (Set between alignment 18 &19)
19. Reactions and Breaks: Buffy's injured and the guys handle it. Then they do something harmful to all of them.
Journal Series: Legacy Journal: Daniel Osbourne: (Set during alignment 19)
Journal Series: Legacy Journal: Xander Harris: (Set during part 19)
Journal Series: Private journal of Derek Rayne: (Set between alignment 19 and 20)
Journal Series: Legacy Journal: Buffy Summers: (Set a week after Buffy wakes up)
Journal Series: Legacy Journal of Daniel Osbourne: (Set six months after leaving house)
Journal Series: Legacy Journal of Xander Harris: (Set four months after alignment 19 ends)
20. Healing Wounds: They come back together as a family and as a house.
21. Mending the Breaks: 'Ship stuff here, working it all out, well mostly.
22. Fully Healed: more Willow/Oz/Xander 'ship stuff here, working it out
23. Illness and It's Solutions: Xander's reinfected so they cure him and he does something really bad.
24. Admitting it to Them: The group goes back to Sunnydale and ends up having to fight again
25. Oh, Hell, Not You Too!: (NC-17): Xander's predatory instincts come back out.
26. Fixing It. Again: (NC-17) Willow and Oz fix Xander and life happens.
27. Yup, Not a Good: A strange spell takes over the entire house and Xander must cope with it while his mates are away.
28. Fights and Repercussions: The trio fight while Xander recovers and things are said. Nick starts to figure some things out.
29a. Visitation: A P:tL centered piece-Nick gets a nighttime visitor and they have to go help Philip.
29b. Bad Timing Xander's vacation doesn't quite go how he expects. (Rated R for major angst) Takes place around 29a, before, during, and after.
30. Necessary Things: (NC-17) The boys get what they need to go to Florida and Xander makes a decision that will affect them all.
31. Bonds Formed, Mates Declared (NC-17) Derek, Xander, and Oz travel to the Keys to start work on the dig.
32. Family and it's Problems: Xander and Oz meet Derek's Mother officially, and a surprise event happens at the house. Xander and Nick talk about families. (warning: discussion of child abuse/molestation) NC-17
33. Issues: The boys go back to Nevada to deal with the stupid law and end up helping the town. Buffy gets some shocking news, as does the family. PG-13
34. Decisions: A new Judge has to make some custody decisions. (PG-13, some angst)
35. Screwing the Family Tree: Consequences of prior actions and the Legacy Family Tree gets just a little more complicated (PG-13)
36. Lucky: The Family goes to Vegas for a wedding and the boys find a very helpful token. (NC-17)
37. Back to the Real World: The boys head back to Florida with Junior, stopping to play on the way. PG-13 (last happy one for a while guys, fair warning - 3 angst filled ones coming up).
38. Reconstruction: (NC-17, HEAVY ANGST) Xander and Oz get some news about Willow, and they have a bad fight.
39. Nature's Inequalities: (GRAPHIC DEATH OF ORIGINAL CHARACTER.) NC-17/R. Morning after Reconstruction. One of the grad students goes into labor. The family meets a new friend who's aid they come to.
40. New Members Joining: (Death of minor character mentioned, non-graphic.) NC-17. A tragedy hits the house and a new member is gained, his long life experiences coming to aid the house.
41. Old Friends, New Friends: Ray's old friend shows up to deal with his personal demons and the house finds out that some things did/will happen, no matter how much the participants wished they hadn't.
42a. Problems with Leave Takings: a new prophecy hits the house after Philip and Nick start their road trip, and Xander has to make some decisions about his and Oz's relationship based on a dream.
42b. From the Guardian's Side: (NC-17) Events from part a seen from Philip's side. How he's called and Nick's reaction.
42c. New Girls: Buffy and Giles go for Flame, the next Slayer.
43. Legacy Pack (PG) Watch Xander deal with life without Oz. Watch Oz do a little training. Watch Xander and Buffy drive everyone insane.
44. Home: (NC-17) Oz comes home and the house deals with a few lingering problems in their own special way.
45. Set Ups: We come upon the crucial birthday.
46. Getting On With Life: After the birthday, how does everyone cope. The boys take a vacation and some news comes out about health matters.
47. Hearings, Nothing More Than Hearings: Problems arise on vacation, a nasty one that may ruin everyone's lives.
48. Trial and Error: The conclusion of the trial and life goes on.
49. Happy Knots That Only Bind: The boys get their surprise anniversary present and work on getting back to normal.
50. Slogging Through It Until You Reach The Surface: (Heavy Angst Warning) We find out what's really been going on for the last few parts. Some futures are planned out, maybe.
51. Trouble of the Motorized Nature: (NC-17, graphic sex and blood afterwards) Nick and Derek finally get it together, but not without a price. William's attacked and an old... friend comes back to help Derek find the demon. And GRADUATION!
52. Rome, Sweet Rome: Brandon's time in Rome is very useful, to the priests. Philip has to show up and proclaim and prove what he is to save the Vatican from ruin.
53. Traveling With Troublemakers: A story expanding/setup story. Derek loses William and Barbara to an alien, and a new little person needs help.
54. Old Friends Aren't Necessarily Good Ones: Some things about the dig are discovered while Junior's ill. An old friendship is tarnished.
This Series Ends, but another is coming to take it's place.