If it where me Id seriously consider some active speakers that allow for tuning of there sound though it seem like you would like to keep the arcam and Cambridge audio MX.
If you did look to the left there are a few they could would work. Just food for thought nothing more
for example and they do a 30 day home trial.
Active Bookshelf Speakers
buchardtaudio.com
And dare I say as it's a very dirt word! as long as you dont need legacy connections and becasue you're putting them in such a compromised position anyhow id take a good look at the Sonos era 300's or play 5, it really would be all you need in that comprimised spot. Using there true play feature would actually sound surprisingly good. They also do a 60 day free trial think
And you say your moving in a year so id say save your cash and get what you really want in a year in the new space.
Then you have the devialet phantom speakers they do a small one.
again just food for thought.