Based upon the fact that RTG Pellets are required for high-end items, and since you need plutonium to make those, the clear path to take in the Infinity modpacks is to spam IC2 nukes. I used multiple one-block nukes that output 120 EU/t each, so I split them into groups of 4 and connect them to an MFE (4*120 EU/t=480 EU/t and the MFE outputs 512 EU/t).
So that obv takes care of the EU side in terms of power. You could spam 800 of the things very easily, then your big task would be obtaining enough uranium to run them all. Each nuke requires 2 Quad Fuel Rods.
But for RF, that's easy as well. Put an Immersive Engineering HV connector on the output of four MFE's and run all four lines into separate faces of Thermal Expansion Tesseract. You now have (512*4)=2048 RF/t from each MFE, and total of 2048*4=8192 RF/t coming from your Tess.
tl;dr Focus on IC2 nukes due to plutonium requirement for high-end items.
The reactor I spam is the second reactor listed in the second post in this thread on the IC2 forums, the one that outputs 120 EU/t, look at the screenshot to see the internal component of the nuke:
http://forum.industrial-craft.net/index.php?page=Thread&threadID=11729
And best of all, it cannot blow up, so you don't need any shielding. I run them right in the middle of all my stuff. Living dangerously. hahah
i had one blow last night but it was due to a bug. Apparently if you use a dolly when the all the components are inside most of those components will disappear. Iuckly only the reactor blew and didn't damage anything else. I do agree tho get reactors up asap and expand when possible!