Buildcraft: Beta for 1.8.9, IndustrialCraft: Alpha for 1.8.9, Galacticraft: None, TinkersConstruct: Release for 1.8.9 to 1.10, Railcraft: None, Computercraft: Release for 1.8.9, Alpha for 1.9.4
Also: This server runs on a combintion of Forge and Bukkit, without bukkit there would be no Lot-Protection or properely working dynmap. At a later point we may can upgrade to 1.8 or 1.9 or even 1.10, which is no problem as some plugins are available with Sponge already.
It really depends on the choices. I would not like to miss out on any of these mods.
I mean i've spent a whole day on just searching for mods that fit to the automation community best and findout which versions are available...
On the IE/TE Thing... sucks if it adds worldgen stuff, and worldgenretro is not avialable for 1.7.10 unless someone made something similar for it. Thing is: you CAN obtain the new ores there, but have fun finding them... everything beyond ~2200 blocks from spawn can be viable