Need advise on which new truck - 1/2 ton or 3/4 ton?

As far as entering the truck, if you stay with the higher trim options you can add "automatic" running boards. These will extend and retract when you open the doors. In my experience they will drop lower than the fixed style of running boards making it easier to enter.
Its a lot cheaper to order the truck with these than to add them later. Usually costs about $1K as factory option or pay $1500 plus install after the fact. The ones from the factory will have a 3 year warranty as well.