I myself use poweramps as I need a flat response for audio mixing, which I do on my computer. You could get away with a receiver and it should be better for you. As far as the receiver/s that is best for you, I don't know about all of their inputs and outputs.
I just had a thought and this would be perfect. If you bought an amp or receiver and two shielded bookshelf mains. And then two of the self-powered Roland monitors for the rear. Then you would not need another amp and the sound is pure for the rear channels. Musician's friend has these for $89 for the pair. They come in black and white. These are professional monitors and can be seen on tv in studios and television production. This is cheap and acurate as hell. The perfect solution for rears.
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I don't know your budget, please post it so I'll have more to go on. But I recommend the Paradigm sheilded Titans for the mains. These sound great, are very accurate, and have a lot of bass for small speakers. I use these for my mains and am very impressed. These go for around $200-225 for the pair new. You can use any amp or reciever to power them, just buy something cheap if you can't afford it. But the speakers are more important. Hell a bestbuy $79 special reciever would work.
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Later on you could always add a sub. This system will kick major ass and be easy to setup.