I'm not sure I understand your question. I think you already have a c1 center and two b1 bookshelf speakers and one rsl speedwoofer 12s. Based on a quick google search, this adds up to about $1,900. This leaves another $600-$3,100 before you hit $2,500-$5,000.
Are you asking if you hypothetically should have bought more expensive speakers so you hit the $2.5-$5K budget?
Are you asking if you should return one or more of the speakers you already have, and you're willing to spend $2.5K-$5K to get different bookshelves, center, and sub, with future floor standing speakers going above the $5K limit?
Or does the $2.5-$5K budget include the floor standing speakers you intend to buy in the future?
Does the $2.5-$5K "line up" refer to speakers only, or are you asking the best way to spend another $600-$3,100 on the overall system given the speakers you already have?
What is the intended us of this system? Since you bought a center, it appears that you intend to use this for HT. Is this correct?
How big is the room?
I'm sorry, but I don't understand what you're asking.