power utilisation can be greater than 100%, typically 104% is ok for no manual power-management if you're not carrying cargo.
when outfitting, remember that lasers will not be active at the same time as your FSD - you can only use the FSD with weapons retracted and thereby, powered-down. If you don't have any cargo bays, save more energy by disabling the cargo hatch.
This is my combat vulture:
link
Note that it has cargo hatch disabled and FSD set to priority 2 in module management. I don't need to make any adjustments to modules once it's set up like this, just deploy or retract weapons in normal space in order to jump away.
Hull reinforcement it possibly a bit pointless as just adds weight and I'll typically bug out if my shields are about to go down. Haven't tried shield cell banks with it as stick to solo (PvE not PvP)
[edit] btw. if you are running at 100.5% and not configuring module priorities, then you should be seeing the red
/!\ warning symbol against power usage if you look in the modules tab - so it does warn you when you've crossed the line. It's a shame that you can't see/tweak the settings from the outfitting screen and have to keep popping in and out to find the optimal build.