Revel F228be

You're ready to drop an amount that certainly warrants getting the room prepared to exploit whatever you decide on.

It will be a waste if you can't get them out into the room 4-6ft from the front wall along with diffusion/damping. Fancy speaker cables and footers will NOT compensate for not being unable to meet this requirement.

Your amp and whatever linestage  in use will be fine until can plug in a "proper" 2 channel  amp and linestage. 

Demo highly recommended.

With a $7-8K budget you could probably buy the Revel F226's and a Coda CSiB integrated amp (and keep your SVS sub).

With a $10K budget you could probably buy the Revel F226 BE's and a Coda CSiB integrated amp (and keep your SVS sub).

The biggest issue with either scenario is how rarely the CSiB hits the used market; and, they sell very quickly when they do.

Bottom line, upgrading from the Rotel amp is good advice; so, expanding your speaker and/or amp choices might be necessary. Have fun and good luck!

My philosophy on a system is different than most peoples. You can make cheaper speakers sound amazing with better electronics, but the opposite is not true! Also, speakers are harder to sell than other stereo components mainly because many are large/heavy and expensive to ship. The exception to this rule for me is if I can find an end game speaker that I will have for 10+ years! 

Used Focal Kanta 2 would be a nice one to audition. Good luck ! 

I’d actually suggest selling the Rotel and the sub a just starting from scratch.  Buying a better amp and two smaller sealed subs, even if that means spending a little less on speakers, will yield you much better and more balanced overall sound. FWIW.