You are doing what not many do, which is NOT go from car to ebike, but from regular bike to ebike. Different mindset.
Try a little thought problem. Think of bumps, sudden stops, lots of little things you encounter while riding. Now, for each and every one, imagine you are going 5- 15 mph faster. What do you need? Also, that 5-20 mile ride you take often? Now you do it much more often, and go 10-40 miles frequently.
Light weight is sacrificed for durability. Safety is a larger concern. Heavier tires, more durable rim. Shocks, brakes. Better seat, better seating position. More padding for your ass, as you get more saddle time. Handgrip pads or rests. Because it is easier now, and more fun.
You can buy a hub motor bare, and build your own rim or hire it done. The savings in shipping costs from the smaller box nearly outweighs cost if you hire the work, and you get a MUCH better rim, spokes, and build. Whatever size rim you want. Not hard to do yourself, but tedious.
Something in the ballpark of a Mac or Bafang geared rear hub, 1000 watt, 13S battery, AH is going to be a question. Gets down to where to hang it, and do you sacrifice range for performance, or reduce the motor and get more range and go a bit slower? Or a big honkin DD hub and monstrous power for a dirtbike?
If it is purely a playtoy, and you have major hills to deal with, a crank-drive might be a good option, with some drawbacks.