If you are using cut pieces of wood as opposed to say 1/2 sheets [ read expensive machine ] think about nesting the letters seriously.
I don't mean nesting as in doing J's as spoons but see about getting thinner letters to go at the side of wide sloping letters.

Something like a J upside down, then an A followed by a A upside down and finally another J or L right way up will use virtually the same amount of wood as the two A's.

You also want a CAM program that can leave tabs like Vcarve so all the letters stay in the parent material until broken out and the tabs sanded off. This way it stops damage to the letters and tooling.