415 - There has been a central ( I think CDS) push to improve, but my understanding is that Wigston/Byford pushed even harder (ie, much more than was achieveable).
416 - Cannot answer your point, but here is more detail for 1 April 2022:
RN/Marines Army RAF
Mixed Race 480 1,530 480
Asian 190 3,210 320
Black 880 5,660 280
Other 90 920 70
TOTAL 1,640 11,320 1,150
The Army does recruit significant numbers of Fijian soldiers.