What about a Corvette Z06, which is around 3200 lbs as well? That's about as light as you're going to get with a car with a V8.
That's fair. It's in a completely different league.
Your definitions are all out of whack.
Even the Ferrari Enzo and Carrera GT weighed 3000-3100lbs, which you'd consider "mid-weight at best", approaching "heavy". Porsche Cayman? 2950lbs, aka "mid-weight". E30 M3? 2900lbs, aka "mid-weight".
So, no, you get real.
In fact, here's a challenge: list all the two-door "sports" cars you can think of that weigh under 2800lbs built since 2000.
So the name or the power-to-weight determines if it's heavy to you? Those have nothing to do with it. A pro bodybuilder will be heavy, a figure skater will be light. That's just reality.
As to your challenge (I'm including world cars, not just USDM, and not including FWD sport compacts):
-Miata
-S2000 (I know it's 9lbs over, but fu if you think that disqualifies it)
-RX-7 FD (built till 2002)
-Elise/Exige
-NSX-R
-Silvia
-Impreza (I'm sure you won't count it as a 'sports' car though)
I want to say the Lancer, but in any good trim level, it's in heavy territory)
-VW GTI
-Integra Type-R
-Alfa Romeo 4C
-Fiat Barchetta
-Mini Cooper S
-The Toyobaru, of course.
I'm sure there are more that I can't think of... and I'm sure that there are more in the pipeline.