Have a look at the Bellanca Citabria.... Cheap, able aerobatics, float, glider towing, pleasant to fly... The Citabria is a nice airplane.
Concerning the gliders, you can start with an old Blanik from eastern Europe, quite cheap and well designed.
The Robin is quite fast for this range of price, interesting if you regularly travel (to Africa for example...).
Anyway, a lot of choice.