Thanks! I too am going baremetal, as I prefer 5 second builds to 45 minutes - but yes the board sounds like a bit of a pain...
I'm using my OP2 Oberon compiler version and also my Micron compiler, and both indeed just need a few seconds for the build of the whole Oberon or Micron System 3 and only a few megabytes of source code. Version 6 of IDF didn't even work on my host.
Both. The USB-JTAG flapping is probably a board issue, as is the HDMI integration; and they use the 1.0 version of the P4 which also has its issues. Your link doesn't work from my location, and I don't have experience with other P4 versions so far.