Cool, cheers for the kind words guys (and for the book recs, rpm!)

As I'm sure it is with anything, after you've been doing karate for a while you notice things that have been evident all along but that you've been overlooking. One such thing I noticed fairly late in the piece when I used to do karate was that I spend a huge amount of time balanced on one leg, and that it would have really helped me out to have, right from the beginning of going, pushed myself further into the stances and kata to build up my leg muscles so that they could better support be when kicking and whatnot.
Since I'm now in the happy position of being right back at the start, that's what I intend to do. Rather than trying to stand as comfortably as possible, and adjusting myself when muscles start to hurt, I'm going to really put the effort in to do everything properly rather than half-assed. Most of the things we do have a purpose, even if not self-evident and even if not explained, so there's benefit in doing them to the best of my abilities at all times, rather than a "close enough is good enough" attitude.
Starting small, the first thing of hopefully many is I'm going to make sure that from now on I'm always as deep into my stances as I can be.