I've never done an end pour. The bow from bottom planks up (where the sides meet) has a thin bit of tapered wood (wider at the top) to give a slight rounding to the bow rather than sharp point. The stern, because a rudder is always fitted usually has a small transom.
About 15+ cm aft of the bow a piece of thick wood across the hull that the deck lands on and that a fitting is screwed into. This takes the decklines and lifting handle rope. This is strong enough for more than half the weight of a multiday fully loaded kayak. Half the weight because someone is lifting the other end, either using the aft lifting toggle or lifting by a comfortable hold of the rudder unit.
You mention a glassed hull? Why? Adds a lot of weight and cost unless epoxy is very cheap for you. I don't know how long an unglassed hull will last as my oldest is only 35 years old though our ply pramm dinghy is over 60 years old.
So 3 mm ply with a first wetted (test paddle) weight of 13 kg and finished fully fitted out (rudder, lines, hatch covers, etc.) weight of 18 kg, and that could be reduced.
Strength? If you hit rocks? I always hit rocks, probably every time I go paddling. My partner if landing on a beach will simply power on to it - with an unglassed hull. She does leave grooves in the gravel as the keel has carborundum in the epoxy.
Finish - paint as UV here kills varnish and is even worse on uncovered / unprotected epoxy.