Best way to approach Pi + XBMC + Emulators?

[ArmNALeg]

I've been trying to get the above set up running using a few methods: Raspian, Raspbmc, Retropie + emulationstation, but have run into various issues, and never seem to get xbmc idling less than 95-100% cpu. I've seen Arch users reporting much lower cpu loads, and as this project is gonna be very light (neither xbmc or emulators require X, right?) and I'm SystemD+, I'm thinking of giving Arch a spin. I've used Arch before but I'm new to Arm, XBMC and emulators, so I was hoping for some input before I start over.

My plan is to install xbmc and the emulators individually over an Arch base, and use xbmc's Rom Collection Browser add-on. That way I can (I think) just boot straight into xbmc and control everything from there.

• Does anyone foresee any issues with this plan?
• Has anyone attempted this approach? (Successfully or otherwise)
• I'm currently using xbox360 controllers in emulationstation, is this also (reasonably easily) do-able in xbmc?
• A quick search through the available packages suggests there is an emulator for all the systems I'm after except the sega megadrive, which I guess I can compile that from source(??), however some of the choices are I think different from the emulators installed by retropie, can anyone confirm that the emulators available in the repo's work? (My experience with Arch makes me think that's a stupid question, however my experience with emulation makes me think its worth checking!)
• Has anyone got any better ideas?

Thanks for reading. Any input is appreciated, even if it's just to call me an idiot, I'd much rather be told I've got things wrong ,than waste my Sunday finding out for myself.