If you were the salesman in the store and I walked in looking for something to drive 5 Maggies, you probably wouldn't sell me the RSX-1065, right?
So what would it be?
Well, I would first tell you that you should just sell the Maggies to me for a 'good price' and I'd give you something you'd like more.

But that's because I've been trying to work a pair of the 1.6's or 1.7's into my 2CH setup for a couple of years now... but I have a very small house unfortunately.
I think a lot of the problem with the Maggies is not that they can't be adequately driven by the Rotel - I've heard some powered by only 60W and it was still very nice sounding (although not 'dynamic' in any sense of the word).
It's entirely possible that the nature of their sound is problematic for your listening style and your room layout - or that their positioning is off. Although the soundstage they throw off when correctly positioned is pretty incredible - they're actually far more directional than you would think considering their size. I've found that with both planars like the Maggies, and with Electrostatics that I could pretty much change my vertical position within the sweet spot and enjoy the same incredible sound - but just moving 1ft to the left or right and the whole image falls apart (for me at least).
Although you could definitely power them for better impact - I've heard/read lots of Maggie owners rave about 1000W ICEPower amps like Wyred4Sounds' integrateds or monos. You could also (for a little less money) use Emotiva's XPA-2 for the front pair and XPA-3 for the center and surrounds. You'd 'only' be feeding your front pair 500W but that's enough to get them singing for sure.
The real issue is that although the Maggies love power - they don't need it to sound like they should. So if you don't like the way they sound - i.e. if the problem is more than a low sustained volume level or somewhat lower dynamic swings that you'd like - then you probably should make the 1.6's a stereo pair and get them a nice amp - and keep the Rotel and get some box speakers of reasonable sensitivity for your surround sound system.
I'm a huge fan of Maggies - but after critical analysis of what I liked and what they needed in terms of placement, power, etc... I decided (for myself at least) that they just weren't a good fit for my theater. But you can bet there will be a pair in my 'man cave' one of these days with a huge lovesac stuffed in the middle of the room between them!
I may have missed it, but what are the dimensions of the room and what do you have in the way of subs?? Because if your Rotel is trying to get the Maggies to play anything under 100Hz that's one of the first things I'd try looking for solutions.