Side question since i play on a private server: Why would anyone make a 'multi level' MFR farm? In an infinite world, why is space an issue? How much space does a person get on a public server, and if its small... what do you mine for resources? Why dont people just travel far away, til they dont have close neighbors?
1) Griefprevention
2) Chunkloaders
3) Aesthetics
Personally, I can't find a good use for more than about 1000 MJ/t or 2.5K EU/t. Perhaps I'm not being creative enough.
Yeah, you aren't being creative enough, no offense. There are several uses for massive amounts of power.
1) Extra parallelization on your current machines. Running the full set of bee machines takes up 300 MJ/t. If you make copies so you can do multiple inoculations at once, then that can get up to 600, 900 or even 1200 if you are doing 4 at the same time. Or running MFR lasers. Sure, one laser is only 400MJ/t. But why stop at one? Why not do 2, or 3, or 20? And hey, while you're at it, why not get enough lasers on your assembly table to make diamond chipsets in a second. And why not make MULTIPLE assembly tables so that you can automate it and have a table for each thing you want to make.
2) If you are doing EU, then you want to make a Mass Fab. And you want that Mass Fab to work fast, and not spend days making each piece of UU-matter. Why? Because with the power of UU-matter, you can shut off your quarries and make what ever item you want on-demand. Push a button and get any item in the game instantly.
3) Powersinks. AE is a prime example here. If you want your MAC to be large enough to contain EVERY pattern in the game and also produce any item in fractions of a second, it's going to draw a ton of power. The same goes for overclocking IC2 machines.
4) Bling. Part of the fun of FTB for me is being able to build crazy structures that would be impossible (or just really tedious) in vanilla. And if, let's say, I want to make the wall of my entire 7x7 chunk base out of lapis, diamond and emerald blocks, I'm going to need a LOT of power for fabrication.
Honestly, for me 2.5k EU/t is chump change. That's just about enough to get a mass fab running, but not enough to do anything really INTERESTING with it.