Most shotgun and rifle stocks are too long for most users as delivered. The old guideline of resting the buttplate in the crook of the elbow and seeing if one can comfortably reach the trigger does not take into account the pull-lengthening effect of heavy coats or body armor.
It is easier and more comfortable to handle a stock that is too short than too long. If the shooter "crosses over" with his thumb, he must take care not to smack his nose with his thumb upon recoil.
The heel of the recoil pad should be rounded to facilitate snag-free and quick mounting of the piece. Whether there is any benefit to changing the angle of the butt-plate is beyond me. The elaborate "try" guns of the high-dollar shotgun makers allow for adjustment of this angle, so perhaps there is some advantage to be gained.
I have no idea if your particular synthetic stock is amenable to easy shortening. I reckon you'll need to remove the butt-pad and have a look. Most are hollow, so it may take a bit of ingenuity.