Brandon,
my suggestion is to try one with a large T1 or T4 in it - preferably both. When I dreamed of spyder ownership 15 years ago, I thought the same about having the most hp per pound I could find. I have a 911 and a spyder and in my opinion, the spyder is a nice fit for a large four cylinder. it has nothing to do with age. The design is what it is, and if the massive horsepower is going to get you into trouble or is tough to manage, then you won't be driving the car much or enjoying it's limits maybe.
drive before you try - that will really let you know what suites you best. contrary to the statement above, it is not too hard to put hp into this car, it just takes money.
Whe I got my spyder many years ago, Chuck Beck took me for a test drive in one with a large T1 in it (about 150hp). we accelerated faster than I ever had and it was a blast - it fit the car right. I put in a 2165 or thereabouts and it is plenty scary fast to get me into trouble. The sensation is awesome.
I admit I would like to try a large raby t4 too, but I am motivated to add a killer V8 to my garage.
So, how old are you keith? and what have you been driving lately?
Regards,
mike