I enjoy these threads, it shows how different people are in their preferances, and that there is no right or wrong way to do it.
OP yes, you could have the cooktop changes out as long as there is enough space below and on the sides, and if you love everything else about the rv it would be worth doing.
I love having the convienence of the stove/oven, sink, fridge, cupboards all in one place rain or shine. I cook for our family of 5, (and have cooked for as many as 9), with the kids having some differing preferances, so our 3 burner plus oven gets a workout every trip. Plus, I pride myself on completing all parts of the meal at the same time. Everything is hot when it is served.
Typical breakfast - seasoned pan fried potatoes, which have to be started first and take the longest. Next is a full pound of bacon on the broiler pan with the oven set to broil. Bacon is SOOO GOOOOD cooked this way! Pancakes for the kids, veggie omlets for us. Yep, that is 3 burners and the oven going at the same time! Or a typical dinner. Steaks in the broiler for us, pot for mashed potatoes, pot for steamed veggies, and a pot for mac and cheese for the kids. Yep, oven and 3 burners!
I would not be satisfied with fewer burners or just a cooktop. And since we drycamp a fair amount, a convection / micro would not be usefull.
Good luck!