i have a few suggestions for you:
im not sure if im fully understanding exactly what your trying to do here and why your mpc is filling up so fast, but ill try my best to give you some examples you could research. are you not able to just use 4 kits or so a night? or are you sequencing whole songs on the mpc and just doing guitar/vocals live or something over top? is that why your ram is running out?
in your other thread thats why i was suggesting midi loops in combination with a smaller sample footprint (ie four kits on each bank), but it looks like you might be needing to sequence more than just drums on your mpc? if thats the case then maybe not an mpc would be the best? although it might also be possible to have your 4 kits in the mpc, sequence them, or use the pre made midi loops, then and on a new track, midi up the bass (and other instruments for that matter) from a different soundsource such as a motif rack or another sampler even.
in your other thread, you said that midi loops sounded repetitive and canned to you, but the beauty of them is that you can edit everything within a midi loop so it wont be repetitive if you dont want them to be.
in most of these midi packs, you buy one that is a certain style of music, and it has thousands of loops for that type of music. intro, verse, chorus, bridge ect ect.
thats why i was thinking it would be a good idea for you to look into those. it makes it so you can just take an intro, chorus, verse and just drop it right into your sampler, then just assign your drums to the same notes 1 time and your set for everything. this will make t so you dont have to spend the time and write a new drum pattern for each song, and if you want to make some small changes, its easy to do that too.
there is no reason why the midi drums should be repetitive or boring at all and im not sure why you were thinking that. the only way i could see them being repetitive is if you just had a 4 bar drum loop and repeated that for the whole song, but with these midi packs, they are tailored to be drum tracks for whatever type of music.
another thing you might want to think about is if you do only need drums and bass, have you thought of a drum machine as opposed to an mpc? i dont know how realistic people get these sounding as i dont do any live shows, but it seems that people use these quite often in their 1 man band setups. it might save you a lot of money too because they are usually pretty cheap.
alternately, have you thought of finishing the whole song(s) and just having a stereo .wav file of the backing track and you can do your thing over the top of it with guitar/vocals? i realize this may take a long time because your set is so long, but dont you have to go to the gig with something like this already? if you had your songs pre made like this, you could even just put them in intunes and run through a playlist of all your tracks like this. if you have intermissions, just put a song with some silence in it and pause it before you get up to get your drink or eat or whatever.
if you are looking for more realism than a drum machine, another thing to think about is a software drum program. there are drum programs like battery 3, bfd, ez drummmer ect. that might be something to think about. they are built to give you realistic sounding drums without a real drummer. again, they also make midi packs custom tailored to these programs, so there is no excuses for getting something that sounds repetitive or boring.
i use battery 3 for a lot of my drums (in my hip hop beats) and they have some great acoustic kits, but i think that bfd or ez drummer might be better for what your after because from my understanding, in one of these programs (or maybe both) you can mix in "room" tones and overheads for some of the kits which might be the added depth that your looking for.
also check this article out, its tips for more realistic drum programming:
http://www.soundonsound.com/sos/sep10/a ... m-prog.htmhope this helps.