The problem with these "Jack of all trade" modpacks is that when it comes down to it you don't NEED many of the mods and are excluding large parts of your audience. As much as I see the logic behind the idea that "mod variety = more fun" its not necessarily true, people will do what they need to progress. no more, no less. just because you have 400 mods doesn't mean they are all going to get played, because they are not necessary to the playstyle of the modpack or the player.
i know, but. for some reason, i just dont like playing modpacks that dont have all the mods im used to. i realize when theres something missing while playing a pack, and when its not there, i just cant continue playing without. like seeing a good modpack, but realizing that it doesent have metallurgy: i gotta have metallurgy, and by extension extratic, because if i dont, how will i get a whole lot of vyroxeres ore or all the other stuff to make armor and tools out of? and vien miner to make mining quicker and easier, and less of a grind. and rotarycraft, cause of all that absolutely brilliant end game stuff, even though i may or may not get to the end game stuff, i just cant play without it.
1.7.10 is much laggier then 1.6.4. No one would be able to run the pack.
If you want something huge I suggest you look up resonant rise. 300+ mods.
last time i checked, it only had 256 or so. and it was good, but.... hmm. idk why i stopped playing it, but it seems pretty good. my expectations on what i consider acceptable, and what im playing currently fluctuate, but for whatever reason i stopped playing it, i should probably try it again. although now, the real problem is that damn 4096 block id limit. 4096 blocks is just way, WAY not enough. i found a modpack with 382 mods, and im trying to add 2 more, but i cant because of the too many IDs exception so :/ . if only i could use more than 4096 block ids