I don't know the Katana to fly but the RV4 is a great little fun machine. You are obviously a prudent person and, with the right attitude, a 75 hr pilot could be safe: just make sure you get some decent tailwheel training, and take it carefully while you build confidence.
Having said that, I would look closely at some of the better VLAs etc. For example, I don't know how much a used Tecnam Golf or Sierra goes for in your part of the world. I've owned or part-owned a number of aircraft and would not go back to the Lycosaurus world on the aircraft for which I am paying all the bills.
In terms of performance, with a Sierra you get your 100+ kts on 16 lph of Mogas, with 5.5 hrs endurance. Bubble canopy, open in flight if you want. The biggest downside of the VLA for me is no aerobatics. I quote the Tecnam as an example I know, but there are probably others to look at - although maybe not many if you want to stay in the EASA certified world. (Do you?).
Worth a thought, anyway. Let us know what you decide!