I'm a bit short on hands on experience yet because I'm at a similar stage to you, ie., planning. Here more out of interest than offering any advice sorry, but nevertheless have some comments/questions. .
Is any of the hardware you've listed existing.?
The TP Link AC1750 you mention are wifi range extenders. I'm pretty sure that's not what you want. . https://www.tp-link.com/au/home-networking/range-extender/re450/
probably one of these?
https://www.tp-link.com/au/home-networking/access-point/
I've been leaning toward the Ubiquit gear. Apparently great perfromance from their WAPs and good user interface. I got the impression they're very capable and configurable, but also OK reasonably easy for non-IT people. I'll be changing from Apple Airport Extremes, which are dead simple, so I need something good for dummies.
My current plan is the start with a Dream Machine (router + WAP) in central location and see if the better wifi signal from this one unit is good enough, then add more WAPs only if necessary. Or, the Dream machine Pro out of sight and a separate WAP (for higher WAF).
With the right bits I think you could do away with the switch. Some ubiquiti WAPs have a secondary ethernet port which you might be able to connect one of your wired devices (TV,PC) , or to another WAP. Passthough of POE may be an issue so best not take my word for it. .
I think you're right on both points. Best to future proof. make sure it's solid copper too