Ignore the option of the 5D3
for the kind of photography you do the 5D2 is the perfect option and is in a reasonable price range.
I've used both in a studio situation and I can personally say that right now at this point in time I could never justify spending all that extra cash on a 5D3 when they perform identically (literally) in a studio setting. It's just not worth it when the 5D2 is still a bloody fantastic camera - sure the 5D2 is famous for its not-so-great AF system but for me that's not an issue since I manual focus 99% of the time.
Sure, you're not doing studio work but you are doing landscape and macro - neither of which you need an excellent AF system for and nor do you need it for architecture. People & Street - maybe, but still, the AF system is perfectly adequate for this kind of work and getting a 5D3 just for the better AF system isn't necessarily going to better your chances of getting "the shot" - that comes down to practice, practice, practice.
5D2 is the best option for you to go full frame, the cost is excellent for brand new bodies as used bodies are within a few hundred $$$ of that price anyway.
Don't get lured into the 5D3 by all these guys that have jumped the gun! (Most of them have been complaining about the camera in other threads anyway )
This is where the 5D III is shine: indoor and outdoor & day or night & still or fast shooting.
I had 5D II for 3-4 months. I couldn't stand the AF system and fixed 400 Auto ISO in M mode.