SYSTEM 15 (plus a few extras) build - requesting advice for the layout

Could someone please give me some advice on fitting this SYSTEM 15 together? I have a few extra bits, so following the 'suggested' pattern does not quite work, nor the fact that I am building into 84hp rows...

I'd appreciate whatever input you could provide, as this one is beyond my knowledge to date. Thanks!!

EDITED Wednesday August 14, 01:38

I've actually bought the rest of the modules to make this into a SYSTEM 55+ (with 8 x VCA and 8 x EG). I'll update my design when I get a chance - still looking for advice, just not at this exact second!