What would be a great match for my Paradigm Eclips

I am currently updating home home theatre system. I have a pair of Paradigm Eclipse speaker's that are in immaculate condition. In my research I sense these are great speaker's and probably should not be replaced.

I was looking for recommendation's on a new center speaker that would match?

Paradigm has a LCR 450 would this be a good match?

I currently have old Definitve Technology BP-2 rear speakers. Should these be replaced or does it make a big difference?