If I was starting from scratch I would get a deck either like this one or the Blue One and also some @Boardnamics 145mm hangers (if single drive) or Boardnamics 170mm hangers (if dual drive) unless unobtainium then Boardnamics 184mm hangers. I would not use 220mm.
10S is great for tools and 12S is great for toys but it just depends on your goals.
I don’t like the Maytech motors that much although this pair is still running great after I modified them. No issues afterward.
These FSESC 4.20 have been running great HOWEVER I have been running them at 10S and 21.5A battery max per ESC. If you run them higher you may not have the same results. This skate still has tons of power, can get up any hill, and can stop on a dime, even for a 100kg rider.
For mounts I would use Boardnamics mounts yes. They have some short ones that are very nice.