In the interest of the best possible agility for all planes, from this means, this is a wish for revised fuel tank filling/draining orders and corresponding distribution in fuel loadout choices (25/50/75/100%) for any planes that need it (like the P51 and Fw190s got). Suggestions welcome... I'll start:
The mossie would benefit from the outer tanks being filled last and drained first. IIRC they're slightly ahead of the inner tanks, but most significantly outside of the roll axis. I vaguely recall the AUX tank also not being a clear cut case, so a "safe" bet would be wishing for the only change to be the outer tanks; until someone shows a schematic (I know there's at least one, but lost it) to answer this detail.
The Ki84 would probably benefit from the wing tanks filling last and draining first.
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