You could always try learning new things as part of your hour-building, thus forcing yourself to fly with instructors regularly. I'm hour-building now, and found several bad habits needed to be beaten out of me (literally, by one instructor!) as part of my tail-wheel conversion. So far, the complex aircraft checkout and the night-flying haven't shown too many new bad habits that have come in since the tail-dragger, but there's always the aerobatics that I've got booked for later this month. And of course you could try sea-plane ratings if you live somewhere appropriate, multi-engine ratings, checkouts on new types (the more varied the better, not only because of the range of experience, but also because you'll spend more time with an instructor...) The best part about all this, I'm finding, is that this is much more fun than flying Warriors for 100 or so hours after getting your PPL!
(Oh, for anyone who was following the old thread on solo night flight in the USA - sorry for not replying, been very busy. Seems that if you come to the States without a night qualification, it is not possible to solo at night in the USA unless you get a FAA student license and all the associated hastle. Several people told me this, and several other people told me otherwise, but I found the appropriate FAR which confirms it - can't remember the number now though!)
Have fun!
FFF
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