the Ki-100 was not just a marginal improvement over the ki-61 airframe it used (which by the way is a honey of a plane)
Here's the Ki-100 in a nutshell
1) Ki-100 could dive with P-51 Mustangs unlike most Japanese fighters and hold the speed on pullout
2) Ki-100 had double the 20mm rounds with the cannons mounted in the wings
3) Ki-100 had an initial climb of 3,300 ft/min
4) Ki-100's radial engine (about 1,500hp) proved far more reliable than the ki-61's v12 (rated at 1,175)
5) Ki-100 was lighter than the ki-61 - and this weight reduction with an increase in HP would lead to faster acceleration performance
6) In one encounter over Okinawa, one Ki-100-equipped unit destroyed 14 Hellcats without losses to themselves
7) empty weight is lighter than the La-7
Overall a really great airplane
and excelent companion to the ki-100 would be the Mitsubishi J2M "Raiden!!!
I absolutely LOVE ugly planes and the Raiden was damn smurfy
here's the raiden:
