Sanderxpander
It has got some really good drum samples, a great way of editing/modifying kits and sounds, and (depending on which sets you purchased/selected) lots of live played midi grooves.
SessionDrummer will accept any samples and also comes with (and can integrate any) midi files. It will play multilayer round robin or randomly selected samples, will play different samples according to any CC (modwheel for example) allowing for example live snare or ride cymbal articulation or sophisticated rises.
It can pitch shift, has amplitude, pitch and filter LFOs, has envelope generators, has a 3-band EQ per instrument and a bunch of esoteric stuff for creative moments. You can even select different samples depending on the NOW tempo! (Why would anyone want to do that? - Dunno. But SD can do it...)
And as for editing, well, SFZ is just a text file. Copy/paste entire blocks of ideas from existing files into yours.
AD clearly is good, from what folks say. But sometimes we forget what we already have.