I was going to suggest a couple of things, but then as I kept reading, I discovered AerBabe has beaten me to both! Great minds think alike - or fools never differ, one of the two.
There's no doubt that learning to fly a tail-dragger will improve your landings. It won't help deadside joins so much, but it will open up a whole new world of interesting aircraft for you to fly!
The other thing I was going to suggest was the night qualification, especially since it's much easier to get this during winter than summer, so if you pass on the opportunity you won't be able to change your mind until winter 2003. Again, you'll spend a lot of the time in the circuit, so it will give you a chance to improve your landings. You'll go to other airfields once or twice, so you'll get a chance to practice joining with an instructor, as well as navigation. And I found that the completely different appearance of a runway at night time helps view runways in a more "abstract" way, which makes landings in any conditions easier - kind of hard to explain, but it forces you to go back to those techniques of seeing if your landing point is moving up or down in the windshield - techniques which, if you were anything like me, you "learnt" for your PPL but never really understood.
Whatever you decide to do, though, have fun - 3 or 4 hours a month sounds like more than enough flying to stay safe!
FFF
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