I think, given what's out there right now, your solution is actually going to be in two modules...
Said two modules are in this build: the Erica Drum Sequencer and the 1010 Music Bitbox 2. This setup allows you to change patterns, sequences, etc on the fly with the Erica, and the Bitbox also allows you to trigger things manually by tapping its touchscreen, in addition to its 16 trigger-ins which matches the Erica's 16 trigger-outs.
Also, since the Bitbox can sample, I placed a Ladik stereo input in front of it. Then, since drums like 'punch', I added a WMD MSCL stereo compressor for the Bitbox's output. Handy metering device next, then a Happy Nerding Isolator, which gives you not only a stereo output at line level, but also transformer-isolates the rig's audio outs to help avoid ground loop and noise problems. The Erica Drum Sequencer isn't priced on here, but if you check their website, it's actually 600 EUR. Slap this mess in a suitably-powered 84 hp cab and it's done for about $2k, maybe a bit less. Should be the sort of thing you're looking for...plenty of on-the-fly playability, buttloads of storage for samples, kits, patterns, and sequences, and compact enough to stick in a backpack, more or less.