Possibly related to <ReactorStabilizationPowerEffectiveFull> or another config value recently added. The max regen is equal to a single functional reactor block and does not get past that. Changed plenty of config values but had no luck in getting any increase beyond that single reactor block.
getStabilizationPowerEfficiency() is wrong, it's using actual stabilization values and a ratio together, returning 1 stabilization at the end anyway which explains the 1 reactor regen.