Opinions on the right Aerial Acoustic and amp for a room?

I am a big Mike Kelly fan, and have had several ADS speakers in the past.

Now that the kids are grown, I'm looking for a set of Aerial Acoustic speakers for my finished basement.
Dimensions are 24' long by 20' wide with a 7 foot ceiling.

Unfortunately price is a consideration, so I wondered if the 5t bookshelf speakers would be enough for that room, if I should wait and save for the 6t, or shop for a used 7b?

I also currently have a Yamaha R-S700 Receiver, so any thoughts on the right amp to drive those speakers would be appreciated.