Lotus Elise isn't that expensive, you can find a VERY lightly used one for around $40k, that is well within reach of the common man.
I'm not a fan of the 350Z convertable because I think it suffers from the same problem as Porsche 911 cabriolets. Their ass end is really bulky and to me isn't very appealing, just doesn't flow well in my eyes. Solstice is somewhat aesthetically pleasing but I've never been a big fan of Pontiacs looks in general, I think the front end is too buggy looking. Personally I like the S2000, which is also why I own one. Great lines, decent power, handles well, lots of potential, big aftermarket, Honda reliability, etc.