Used Logic for a year, switched to Live 8 (and free update to Live 9) and never really looked back. Live is probably the closest thing to Reason in terms of sheer routing flexibility (not sure about FL but you don't want it anyway), the racks are incredibly versatile and are by far my favorite feature of the whole program. The workflow is super fast as well, especially with the way that it integrates plugins into the device bar at the bottom. I also quite like the piano roll, while people have complained about it my only other experience is with Logic's, which was cumbersome as all hell. The one real downside of Live is that it's minimalist compared to Cubase from what I've heard (certainly minimalist compared to Logic), but what it does it does better than anything else IMO. Another downside is the fact that it doesn't compensate for plugin lag with automation, so if you chain up a bunch of effects on a single channel your automation can go out of time slightly. It's a pain in the ass, but I certainly wouldn't switch because of it. On the whole I imagine that Reason re-wired into Live would be a killer combination, give the trial a run and see if it works for you.
If you're willing to wait a bit you may also want to take a look at
Bitwig Studio, which has been in beta for a long-ass time and is expected to come out sometime this summer. It's a new DAW by some old members of the Ableton team and it shows, it looks like Live on steroids. It's got some features planned that aren't in any other DAWs at the moment, shit's insane
edit:Oh also, I just realized that you're probably going to want to buy some plugins if you end up going with Live. Live Suite is pretty expensive and the only two instruments that I ever use from it are Sampler and Operator, which are nice but probably won't suit all of your needs. I suppose you could re-wire Reason in for everything, but then you may as well just stick with Reason.