HRM reality sound check. Can it be better?

[Tonegeek]

(amp is Skyliner, HRM, BM PI, 50 watt EL-34)

I always assumed the fattest sound I could get from my HRM was with OD, mid shift, and PAB on so I tweaked my amp for that. so this is what i ended up with:

OD only sounds mostly like the clean channel only with a little less bass and more breakup
OD+Mid Shift about the same but louder and more overdriven, maybe slightly more middy
OD+PAB is louder and definitely more middy (not unlike a tube screamer)- my least favorite
OD+PAB+Mid really fat, louder and more bottom than the other 3 - my favorite

The first 3 settings are limited but I can get some good SRV stuff going with OD+mid shift

Is this typical for this amp? If not, what should I be experiencing?

I would like to:
get more bottom on the OD alone (like the clean channel)
keep it from getting so middy on the OD+PAB setting (maybe the extra bass will fix this too)
Keep the fatness I now have when all 3 are on

my initial thoughts are I can up the coupling caps to get more bottom on the OD alone (already got 5uf across for all Ck) (maybe tweak the HRM bass trim too)

the real challenge seems to be to get the boosts to be less middy. That seems like it would require a different architecture altogether. Maybe I should explore the BM stack and switch the stack out by lifting the mid leg from ground (is this mega-boost?)

just looking at the possibilities...
thanks