Thanks for the responses. I tried to be succinct in my first post since I personally lose interest in wordy posts. I may have been too brief.
Full story. Finished basement with 2 primary seats; 75 inch Sony. Denon AVR 1700h, pair of 10 inch RSL Speedwoofers, Emotiva C1+ center, b1+ books as L/R. It sounds good but the subs over power the little b1+ bookshelves. I don't play really loud, maybe 80db ish peaks but the b1+ just can't keep up. I initially wanted to get Emotiva towers or XB2 bookshelf but I'm nervous about the power, so I'd probably be upgrading the AVR sooner than I liked. This seems like chasing bad $ just to stay with an older 4 ohm hard to drive center. It occured to me it would be easier to just go for an easier to drive LCR speaker set and keep the existing Denon for now. I prefer less bright speakers anyway.
So the dilemma is a larger bookshelf or smaller towers to pair with existing gear. I think the larger df63 would be a little to big for my needs and I'd rather spend $ to get the larger Elac center with 6 inch drivers vs the 5.