We have a princess LPG 3 burner stove/oven, a microwave, and a barbeque. Our boat also has a small convection oven, but I have not yet used it.
When we brought our boat up from FL to RI, we sailed straight through (stopping for bad weather and refueling), so almost all cooking was done underway. I planned all the meals to minimize using the stovetop while moving (even tho we have a catamaran, I didn't want hot stuff splashing around too much). So we had a bunch of oven dinners which turned out really well -- lasagna, frozen burritos, chicken dumpling casserole. Plus there are these fantastic frozen stuffed chicken breasts (made by Barber and sold at Sam's Club in several varieties -- cordon bleu, kiev, apple/brie). These make really good meals served with a stuffed potato and/or salad. When in port I do more cooking from "scratch" but when underway, it's very simple to just shuffle things from freezer to oven to table. Sure worked well for us.