My choice would be a Firefly M260
Swift Aircraft | Firefly Aircraft but if insurance is too much then maybe not - but will it be any cheaper on other aerobatic tourers?
I was talking with an instructor in Belgium at a facility that operates a Slingsby for acro training: the comment was that the a/c is terribly expensive for maintenance, and not really easy to manage for a private pilot.. the Zlin's and Grob's seem to be more economical to run.