For the type of riding you describe, the internal hub is just about right. They really are less fiddly than the traditional derailleur and work just fine. My daughter is getting along just fine with her internal hub, with use very much like you describe.

Personally, I like the looks of the clean chain line that the internal hub has, but that might be just me.

In any case, whatever you choose, be sure it makes you smile. Life is far too short to ride a bike that does not make you smile.