You have very little mileage on your Cam. You should be able to get some decent money for it.
The MX-6 has a nice tight engine for only 170hp. It sounds nice and is pretty low. It's a nice car. The Probe GT came with better suspension and larger rims/tire combo but the MX-6 looked better.
The last gen 240SX (S-15) is nice but underpowered unless you are going to do an engine swap (SR20DET--I think that's right?). There's nothing like rear wheel drive unless it's AWD.

You have more options for greater power with the 240 but it depends on where you want to go. It also depends on the year you're looking at.
As for other suggestions...it all depends on your budget, and what you want out of it?
Good luck.