Bookshelf is just a term.
Here's what we mean by small speakers on swivel wall mounts...the speakers all show now (your front is an "unfortunate" area with the wall having openings on each side.)
The wife should not mind if rears were mounted and done well. (hopefully)
They can be angled and turned towards the couch.
But, of course, you can always just install in-wall speakers in and hope for the best.
View attachment 69244
The RSL's at least can be angled somewhat.
Reference-level in-wall performance. The W25E angled baffle speaker delivers focused, dynamic sound with a clean architectural finish.
rslspeakers.com