I'm sort of in the same boat as the OP @jargey3000 (pun, I know). Much like the OP, we just need the basics and don't go for specialty dining or upcharge services. My first cruise was on Caribbean Princess but that was over 10 years ago. Next cruise was on Nieuw Amsterdam which I loved. Then, we went on Celebrity which I really liked as well (Solstice, Summit, Reflection). I'm going on Nieuw Statendam next month. I've only done 7 day Caribbean cruises.
I think you will find HAL similar to Celebrity when it comes to the 7 day Caribbean cruises. Choose your ship based on the price and itinerary. HAL tends to skew to an older demographic than Celebrity, but that may change with the newer, bigger ships like Nieuw Statendam.