I'm looking for a multiplayer modpack for 1.10 that's very stable (virtually no bugs), content heavy (or at least as content heavy as possible with everything listed here), and can be run without too much lag (above 15 frames/second in optimal conditions) on a very old macbook pro (which sometimes goes below 5 frames/second under heavy load with vanilla Minecraft).
Issues with Attack of the B-Team are that: 1 it's too big, and 2 it's not even close to the minecraft version (which I see you've already stated). I'm looking for something extremely lightweight, but with enough stuff in it to be more than just vanilla with a few tweaks. Attack of the B-Team is certainly not lacking in terms of stuff, but I'm looking for something to play on with one extra person who has not used any mods beforehand. And their computer's more than 5 years old (plus the fact that it wasn't exactly top of the line even when it was new, to begin with), so I'm thinking somewhere around 5 major mods max (major mods would be like thaumcraft, ars magica, tinkers constructs, etc). The only reason I don't just put the mods together myself is because I want to make sure it's stable enough to not encounter ANY game-breaking bugs/crashes/etc.