Which Magnepans for my small room?

Agreed.  My 1.7s are quite adequate for room of 28x14x9 feet.   3.7s are as large as you should go imo.

Smod, They are very different speakers than you have now. They will not go louder but they will go loud more effortlessly. With your subs they will go loud enough. I do not think anyone can argue about the high frequencies. Many think the Maggie ribbon tweeter is the best made.
They will cast a larger image. Like being in row 6 instead of row 20. This alone impresses a lot of people. Some think the image is too big. I am not one of them. Bass is detailed but does not go down that far but you have that covered. They are dipoles and should be off the wall at least 3 feet. Place acoustic foam tiles on the wall directly behind the speaker for the best imaging. Planar magnetics like the Maggies are usually mentioned in the same breath as ESLs. Both have their proponents. They give you the same perspective on the music. I personally think full range ESLs have an advantage. No crossover, much lighter diaphragm and total control of the diaphragm down to the molecular level. They tend to be more expensive and bigger. I would give a look at the SoundLabs 545 which I believe is in your price range. 

Mike

bdp24, 20.7's are big. Soundlabs 845's are HUGE:)

Touche', Mike! I very much agree, the 3.7 is a far better loudspeaker than the 1.7, which I don't much care for (preferring the ET LFT-8b). The 20.7 I have not heard, but the 30.7 I would kill for. Just kidding, FBI.