I find on my server anyways since we started to go with Vanilla servers and also open the Nether that most my users now just build large geo thermal arrays. Now time has passed and screw large Solar Panel Arrays. We now have Nether and lots and lots of Lava to where it can even almost be considered a unlimited resource of it. My suggestion is simple. Just a config option that makes IC Pumps not work in the nether that is default off so that it effects no one unless they decide to use the feature.
This will make me happy and even deep down make my players happy and move away from doing just pure Geo for large power generation.
Thanks
PS: I assume if IC does this then the devs doing BC would probably be more then happy to follow suit bring more balance to both mods