Hadn't thought about the placement of the bass & drums much. The piano is dead center according to BIAB and Reaper (sounds that way on my headphones, too ... maybe check your balance or speakers?) I placed the bass and drums at 30 degrees right and left .... mainly because BIAB did that in the "style" though I dropped their original style piano and a couple of guitars out, so there had been competing instruments the style had competing with them.

https://soundcloud.com/phil-leith
https://www.youtube.com/leithp