That's a tough one, as mods cover many different categories.
If I wanted more blocks to build with, I'd go for BoP. Nice worldgen, more materials.
If I wanted "Tech", it would have to be Mekanism (If TE3 had a pump, then it would be a close call) but I'd have to have MFR to support.
If I wanted "Magic", it would be Thaumcraft
If I wanted more blocks to build with, I'd go for BoP. Nice worldgen, more materials.
If I wanted "Tech", it would have to be Mekanism (If TE3 had a pump, then it would be a close call) but I'd have to have MFR to support.
If I wanted "Magic", it would be Thaumcraft