Yeah it does have a lot of complex delicate mixing to it. I'll take the opportunity to list other music pieces that I'd like faithful MIDI renditions of.

This track has a similar feel to what I desire from the Killer7 music. Chill but with a contemplative rhythm:
DANGANRONPA OST: -1-05- Beautiful Dead – 05:37
— DontBleedOnTheSuits

This track I know could be a MIDI and it may well exist already but I failed to obtain the Windows port of this game:
Desire (PC-98) OST Reflector Yamaha YM2608 OPNA Speak Board version (remastered) – 04:40
— Blaze Rhodon

Another PC-98 track:
Black Bird (PC-98) - Explorers – 04:16
— AccelJoe

Thank you this is very helpful indeed hehe