Am I able to have an hourly protection where it slowly goes down overtime?

I'm not quite sure what you mean. You can have it so protection costs a certain amount per hour, and if they can't afford that amount, then they will not get protection.

If you're wondering if you can say start at 100% protection and then overtime it degrades to 50% protection, then no that functionality doesn't currently exist, makes a good suggestion though!

Yes. The plugin that currently does that is buggy as hell. Would be great if a plugin does that.