Looking for advice on updating our home theatre/sound system in our living room please. Budget $5k-ish.

We currently have a pretty good Yamaha receiver, approx 7 years old, $2k at the time. We have 4 x JBL speakers attached to the wall (wiring in wall cavity) and 1 x centre speaker.

The objective is to have no speakers visible - everything to be integrated/built-into the walls without compromising on sound quality. I'd also like to be able to control via ipad or mobile.

I'm hesitant to go for wireless speakers like Sonos because I've heard the sound quality isn't as good. Anyone who would like to change my mind on this, I'm listening. :-) Have seen a brand of speaker called DALI Phantom that looks intriguing although a bit spendy and would blow the budget. Bose maybe.

Any suggestions and/or advice would be greatly appreciated. I feel like I've exhausted my researching on Google at this stage.

Thanks in advance!