Jim,

Unless you are racing seriously you will gain very little over what you have now by adding anything else.

1. You have a good vario.
2. The 302 logs and drives the computer.
3. XCSoar gives you glide, etc.

For $4000 to $6000 you can get a new system that will be a few percent better. It is like the difference between your Janus and a Duo. 2 to 3X $$$ for a few percent performance.