It kinda sounds like a good idea, but from my own experience, I'd suggest that you try and do everything at least once in the real aircraft first, or at least in a FTD with an instructor.
I've found that using flight sim to practice an exercise really only helps once I've done it for real at least once.
I think flying approaches, and doing tracking and stuff is much different in the real plane cos there is so much else going on. Learn to do it in that environment first, then hone your skills a bit on the PC.
5 minutes with a good instructor is easily worth 10 hours messing about on your own if they teach you the easy way to do NDB tracking for instance (mine did !!).
My instrument rating is going ok so far, and has been based on getting some good solid skills under the hood, on partial panel, and on doing xc and shooting lots of different practice approaches.
Flying flight sim has never much improved my real world flying, but improving my real world flying has done wonders for me in flight sim ... ;-)