Here, you'll mostly get people saying you'll miss out on the magic if you don't stay onsite. If you post to the "Orlando Attractions" board, most people there will recommend you stay offsite.
You say you're not doing WDW every day; do you plan on doing other stuff in the Orlando area? The monorail resorts and Wilderness Lodge are terrific if you're going to spend most of your time at the Magic Kingdom, but if you're going to be going offsite to do stuff they're kind of a pain, because they're way at the back of the resort and it's 10-20 minutes driving before you even get out of WDW.
Depending on the deals going, staying onsite can be a better deal for people wanting a single room. Staying offsite is usually the better deal for those who need two rooms or more; I have yet to see any deal that makes Disney the cheaper option for us. Renting points always costs
more than twice as much for a 1 BR as a 2 BR in a nice resort offsite. And that's at resorts with snazzier water amenities than any
DVC offers (if I liked sandy pools instead of lazy rivers, that would be less true). So staying offsite gets me a bigger unit for less than half as much.
Which makes Disney look pretty expensive.

Whether it's worth it is a different issue, of course. I tend to think it is, sometimes; hubby's less convinced.