Magnepan 1.6 speakers

I own 3.6s.
But i would say the Magnepans, all the 1.6 1.7 the 3.6 3.7 and the 20.1 benefit from really great electronics. and can be used with products that are far more expensive than the Magnepan speakers cost, and sound better from the use of those better products.
I have the 3.6s $5,500 with a Bryston amp $4,700, a Bryston preamp $4,000 and thousands in powerline conditioners and other electronics. No question i could have spent twice as much on the electronics and still had the 3.6s shine.
So i would say the answer to your question is yes the 1.6 would benefit from monoblocks, or a better stereo amp.

I expect at 200 watts into 4 0hms that the cambridge is sufficient for jazz and vocals but underpowered for large orchestral music. My suggestions for 1.6 magnepans from less expensive to more expensive are: Luxman R117 receiver ($300 used), Classe CAP 151 integrated ($900 used), innersound esl 300 mark2 ($1200-1500 used), Classe CAM350 monoblocks ($3,600 used..overkill). I'd go with innersound and add a tube preamp (I use a lector zoe) but the luxman R117 is surprisingly good and a no brainer for less than the price of good cables.

I had the best experience with my 1.6's with a Levinson 335. They need a lot of current and high damping factors to control those panels. No offense but the Cambridge is just not up to the challenge...