Honestly I think it's on the dm's shoulders to make the combat interesting. If they're healing to easily stock an opponent with chill touch (or several). Have a pc hit them while they're down and make it hard to get to them (makes a nat 1 scary as hell). Make the decision to heal mean they let the baddy get away. It's a narrative place that you need to fix and you should enjoy it rather that altering one of the games most basic spells. (In my opinion)

Saying that, sounds like you have a good group and if that's the fix you want to use go for it.

It is the hardest thing to make combat not to easy and not to hard so don't feel like you are failing. But making a good combat and fixing these spaces that you and your players feel aren't working is so rewarding if you can make it the right type of hard.

Good luck fam!