Doktor Avalanche
Bump!

I've got jazz sticks, vintage dry and Fairfax.. What next?

Thinking jazz brushes, black velvet and session percussion..

+1 for Black Velvet.   I have the three Studio Kits, Fairfax 1, Black Oyster and Retroplex as well, and I really like them all.  But Black Velvet is still one of my personal favorites and in some ways I find a bit more flexible than some others. 
 

I have a few ad packs available here... 
 
I've made a commitment to BFD so I've purged a lot of my Toontrack and AD stuff.

My vote...
Fairfax 1 and 2
Black Velvet
...but they are all good.

It's not obvious but if you have both Fairfax 1 and 2 you get a bunch of mixed set presets (called Fairfax Bundle in the browser).  These are some fairly nice combinations of kit pieces from both sets.  Nice bonus if you own both of these.  You can always make your own bashed kits of course with whatever you own, it's a lot easier to have a good starting preset.

I think you're better off demoing the sounds within AD2.  There are more demo tracks available with just the drums rather than demo songs in the Webshop.
 
EDIT: Demos have the headphone icons.

I added the United Pop, MJ Sticks and Black Velvet kits to my MJ Brushes, 3 Studios, VinDry, Fairfax 1, SessionPerc and Indie. Those were easy to pick. I still think I'll add the Black Oyster and Fairfax2.
 
The assortment of Kitpieces makes that pretty easy, too, especially with my Kits.
 
Where I seem to be undecided is the MidiPaks. I've listened to them all a few times and taken some notes, but last night mustn't have been the best time for that. I'll take another crack at it today. I've got Jazz Brushes, Ballads, DryBeats, Reggae, Perc, AfroLatin, Amer. Indie and Writer's blocks, so far. Jazz sticks is about all that I see as "likely".
 
On one hand it's all great stuff and so handy, but I'm wondering which is more useful to me; Songs or Beats?
I'm sure I'll sort it.
Michael

My first 3 were:
United Pop - for general usage.
Funk - for snappier styles (this ADPack shines equally well in many musical genres, that require punchy drums).
Brush - can be used almost in any genre. Stand out among other packs due to multiple brush strokes and snare articulations.

Black Velvet stands as my go-to across a number of styles; it's where I've drawn most of the shells to create the majority of my custom presets/kits.  It really is substantial.  Both Fairfax kits follow closely behind, but I'd like to mirror what Magic Russ said - the original Pop/Rock/Prog kits are quite useful and where I tend to draw most of my cymbals from.  Nice and bright Paiste high hat in the Rock AdPak.
 
I'm downloading United Pop, Retroplex, and Funk tonight with the AD2 Custom I bought over the weekend.  they all sound interesting, too.

Cool, I've never seen anyone else mention the Retroplex kit before.   I haven't used it for real yet, but given what it is I know I will.  

I went back and listen to the Funk kit and Retroplex and am starting to really like them. The Funk is much punchier than I thought and will get it for sure. I didn't really want to like Retroplex but am liking it more and more.