We have always used the park hopping option. With little ones especially, we find they need that break from the parks. Our little one would never make all day and evening without a break. We like to make use of all the resort has to offer as well, eating at the resort, making lots of use of the pool area along with being able to clean up and rest before heading out for the afternoon or evening.
We also like mornings without fp+ with lighter crowds, scheduling our fp+'s in the late afternoon. Staying on site, we find it's not any trouble at all going back and forth. We accomplish more I think because we're rested and refreshed for the evening and can go much longer without wearing ourselves out.
We used the park hopping option before paper fp, with paper fp and now with FP+, with a baby and with just adults. We just adjusted how we tour the parks with each method.
So yes, if you're like us, they are worth it. If what we do doesn't sound appealing, no.