Several points.
1. Wireless anything is subject to interference. The more devices the bigger the issues. Just make sure you understand this. Any wireless device has the capability of causing problems with communication including wireless house phones, cell phones with wireless capability, tablets/pads with wireless capability etc.
2. I would take a look at Anthem even though expensive. The MRX 740 I own was a massive improvement in capability and ease of setup over the Yamaha RXV663 I owned previously. Although I say this, Yamaha also has very capable AVR's that may be feature rich enough for you to consider as well. The Denon you mention is also worthy of consideration. Arcam and Cambridge Audio are also choices that may if the sale is right be a worthy contender also.
3. RTFM the standards. Not understanding them can result in problems that would not exist if you had done your research. Buy components that match a standard. Buying components on price alone that don't meet the capability you want will bite you badly in the pocket book to rectify.
4. Post your budget for all the things you want to upgrade/buy. RTFM here about people's experiences. That can give you ideas for excellence. Not all expensive stuff is great, not all cheap sucks. Go look at my thread in the loudspeaker section for an idea about that. Even though not on your direct topic, that mindset can help you spend wisely in the right places for you.
5. If you can, audition before purchase. I afterwards on bookshelf speakers eliminated two speakers from contention that I was considering.