honestly a rail on a boat with a squared off side like yours and mine look better with a rail...its stupid expensive for a new rail but it is what it is. capping these things is alot of work unless you really know what your doing with fiberglass and have an abundance of time on your hands.
having a pump thats overkill isnt a bad thing at all..do it right the first time and you wont have to do it again for a long time..peice of mind on the lake is priceless fer sher