The Great ReBuild 2010: Paring things down?

I'm struggling with this rebuild. At first I was going to package up all the sims that have been born in the those neighborhoods and share them and then do the same for my edited lots, but every time I load the game to do so, I lose steam fast. I've now settled on only packaging up characters and lots that I absolutely can't do without. So that means any story characters that have already been featured (and one that hasn't — Phi's mystery baby), and maybe some lots (the Summerdream place comes to mind), but everything else will be played through and made over again. That'll take some time, but it'll be far less tedious than piecing it together bit by bit.

I think I'm going to start by playing the fresh megahood to give myself a chance to see what I truly miss from my other game. I'm going to keep my cc (though I'm paring that down quite liberally), but I want to try to use the bare minimum of hacks and things like that. That brings me to my question of the day (and it's a classic one):

If you were going to start over with only a handful of hacks, which ones would you consider essential?