Sure here is the setup, the pic from back of the couch looking at the TV and the shape of the couch with two speakers in the back and one of the rear speakers when placed on the floor vs when its put on a table. Hope this helps.
I see your problem now. That's a problematic couch...Why didn't you get 2 separate pieces from that couch manufacturer when you bought it man? why did they have to be connected to each other like that? lol You could have set your surround floorstanders at 90 to 100 degrees and you would have been good to go.
You spent a chunk on your McIntosh gear, your fronts and center. So, i take it that you have certain audiophile expectations a.k.a you're not the kinda guy who'll put up with a shtbox speaker. So, for those audiophile expectations to be met, especially if you listen to native surround music sources (SACD mixes, blu-ray audio, or if you like to upmix 2-channel sources into Neural X, etc), you need quality surrounds and good placement for surrounds.
If you take these to the ceiling, it will just get worse from there. Any speaker mounted in a ceiling hole sounds like ass. Any speaker mounted close to the ceiling sounds like ass and it doesn't matter if uppity Focal made it or crappity Radioshack made it. It is no mystery.
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I suppose you could a) get a pair of decent bookshelves for your surrounds and put it on adjustable stands (that can clear your couch). But, since you are already worried about knocking things over, you may start to get worried that you will knock the bookshelves over too. In that case, getting a different couch may also work.
The reason i was suggesting the DTS Neural X/Virtual X route is because it can do a pretty good job making you hear the 'voice of god' coming from above without anything mounted on the ceiling. The guys who work at DTS are just a bit smarter than the Dolby dudes. So, get this DTS experience for a base reference (with just your 5 speakers), And then, cut holes in the ceiling, mount your focals, go to dolby atmos and if it all sounds worse, you can take the focals back to your dealer, mount it on his head and leave.
But, if you don't have those audiophile expectations described above (a.k.a you're not too nitpicky), feel free to do whatever works for you man.