polk questions

[Grevlin]

I'm thinking about upgrading my system. One option is to change brand of speakers and re-do most of my system. Another option is to stay with Polk and try to boost the performance.

I'm wandering on how to max out this possible set-up:

Front L and R- Polk tsi500's or Polk tsi400's
Center - Polk cs10
Rears - Polk Monitor 50's
Receiver- Onkyo 606


Is there an amp that I can use to boost the power to the speakers/which speakers? (Just fronts, fronts and center, all 5)

Is it even worth trying to amp up these speakers/ which one's?

Can you bi-amp(Like I do now with the 606 and 50's) those speakers even with a separate amp? How?

Which would you recommend between the Polk tsi500's or 400's?


What do you think?