Some of my sleeping hubs are still getting views, through people clicking the links through my profile - so, I'm definitely not deleting them.
Also, it doesn't actually seem to take much to make them active again, anyway. I had one declared active again just by fixing a typo that I'd missed. So, it might be worthwhile making changes to get them active again. Though, I suppose if they went inactive once, they'll probably just end up that way again.
If you have somewhere else to move them, then it would definitely be worth considering, depending on whether you think they'll actually do any better somewhere else. But, I don't.
So... make some changes to get them active, if you want to give them another chance... move them somewhere else, if you have somewhere to move them. But, if you're happy with what you've written, don't delete them. There's really no point in doing that.