[huzzam]

I'd generally second Darryl's suggestions, with the following change: if you're not a composer / don't use a lot of virtual instruments, I'd go for Reaper on Mac OR Windows. Logic's main strength is its rich selection of virtual instruments, but if you're not gonna use those, I think Reaper is an easier switch from Pro Tools. And the pricing is really really great.

Harrison MixBus is also quite affordable, approachable, and sounds really good, though it's under far less active development. And Studio One would be the other one I'd throw in the mix (sorry) for consideration.

The final option would be to find a perpetual license for Pro Tools, and just pick a version and stay there. No need to update all the time; major studios don't, why should you?