Just some anecdotal stuff on the battery degradation.
I used my 8 Plus exclusively wireless for the past year, and will do so on the XS Max.
I have used wired.. and a fast charge setup on the 8 Plus also.
I'd go grab the 8 Plus and post the screen, but it's packaged up and ready to be sent out tomorrow. But the Battery health was at 94-95% after a full year of wireless charging. (it was one of the two, and i'm on my 4th shot of bourbon atm

)
If you plan on upgrading every year or two, i wouldn't even worry about it. As long as it's a certified charger and not some cheap knockoff..
9to5mac did a test on the charging, wired fast charge on the X was about 3 hours, wireless at 7.5w was about 3:45ish. 0-100% So yes slower, but not a huge difference. Fast charging gives a bunch up front unlike wireless, but then tapers off until full. Wireless seems to be a constant rate.
Again, anecdotal. You decide for yourself. It's not like there are a lot of reports of any brand of phone exploding due to wireless charging..
As for the heat, it can be the charger, a case if you have one etc. I have 2 Bestand qi certified chargers, only gets a little warm. both are 7.5w chargers. Warmer when I fast charge though.
I have one I got from AT&T that I gave to my mother on her 8 Plus, can't remember who makes it though, phone was never even warm. But pretty sure it was a 5w only.