My current character is a level 8 melee/guns hybrid. It works really well. Shoot them from far and then pull out a Sledgehammer/rebar club when they get close.
Super Slam is a must have in my book.It makes life so much easier. Plus it is just funny to watch some Giant Radscorp get knocked over. Any knock down means an easy kill.
I am mostly using rifles for distance (Cowboy Repeater, Hunting Rifle and Service Rifle) and melee up close (Rebar Club/Lead Pipe). I would not bother with shotguns because melee is much stronger up close then shotguns. No need to reload melee!
I do not plan on taking piercing strike. Many melee weapons ignore dt - chainsaw/ripper/thermal lance. Other weapons can blow past DT - Super Sledge/Fire Ax. Now you may need it if you plan to use a low dam/high dps weapon like the liberator.
Lastly, my melee characters life got a lot easier once I started using a 2 hand weapon like the Sledgehammer/Rebar Club. More range. Allowing you to kite some of the nasty critters.