Finally upgraded to Integra 50.5

I finally made a decision on my receiver and upgraded from my Denon AVR1908 to an Integra 50.5. Huge difference and love my speakers again... Was a big mistake buying the denon for the hdmi input and ditching my old onkyo.

I also picked up paradigm studio 100 v5 towers. If I had the receiver alone most likely I would not have bought the towers.

It is clear that my speakers like the upgrade, but I still wonder if I am still lacking on power to run them. I have a total of 10 speakers. Eventually I would like to have a media room in the basement with all of the speakers setup.

Question: Am I able to buy an amp for just several channels or can I just use the pre-outs for the paradigm speakers while using the receiver internal amp for the boston speakers?

Right now I am running.
Paradigm Studio 100 v5
Boston Acoustics VRM-60 - ZONE 2
Boston Acoustics VRMC -Center
Boston Acoustics PV1000 sub

I also have the following not hooked up
Boston Acoustics VRM-50 possible (height or width)
Boston Acoustics VRMX Surrounds
Boston Acoustics VRMEX (1)