Rotti
Fractal Fanatic
Reading through all of the various responses, I can't help but to think that conflicting responses mean that these are great problems to have. In my limited time with the Axe I think the reason I love it the way I do is that the tone I'm going after absolutely can be achieved, and there's a lot of different ways to achieve it.
You've got the right idea.
I 100% agree that the IRs you use WILL make the biggest difference to your tone without digging through adv.params all day long.
...but the catch is that you'll dig through IRs all day long instead, until you find the ones that suit you the most.
I've gone through all the freebies I could find (great stuff already in the box for cleans & crunch tones), then I picked up some of the OwnHammer HGEs and never looked back. For all things high gain, that's the place to look IMHO.
And yes, CabLab is a MUST! It's another can of worms, no doubt, but well worth it, and for the cost of a few packs of strings.