I would do a tailwheel course first
That certainly sharpens up aspects of your flying. You learn to pin the approach speed very precisely and to handle cross-winds properly. A few hours on a Cub will make a tricycle aircraft seem alot easier and the precision is what you need for IMC where there are tolerances of + or - 100 feet in the skills test. Not only that but tail wheel aircraft are some of the most enjoyable you can fly.
The key to rewarding flying is to try different aircraft and develop different skills. The greater variety the better the pilot. And, it does't have to be hugely expensive. Whatever you want to do shop around and talk to as many people as possible.