I'm not a "car person", but I can chime in with another vote for a Miata. DH is on is second and just loves the thing. His first one, he bought used in case he didn't like it. Kept it until routine maintenance was needed (tires, some other things), then traded it in on a brand new one and has been happy as a clam ever since. I call it a "toy car".
If you get down to it, the Mazda Miata is the best sports car to ever be built that's affordable and durable. But it has an image of being a "girl car." My college roommate had a couple of racing Miatas he campaigned out of Florida, and they weren't for sissies.
I think the image of it being a 'girl car' is odd. In my area, it's viewed more as a middle-aged guy's car. Not a crisis car, but a mid-40s to mid-60s guy's car that says "the kids are out of the house and now I can have fun!" In fact, in all our years of driving around in it, we've only ever seen one woman driving one.
We have a 2008 MX-5 (Miata) roadster bought new and it has been extremely reliable and loads of fun. We are thinking of switching, though, because we'd like to take the fun car on trips occasionally and the Miata is pretty noisy, has a fairly unforgiving ride, and extremely limited trunk space. It's a blast on curvy, twisty, roads, but not so pleasant on an expressway. We are considering a Mustang convertible (GT?) but need to confirm that it will be a more pleasant experience on longer drives.
It's noisy on interstates, for sure, but we just load up a podcast. Otherwise, we're on those back roads (actually the divided highways that were the main roads before the interstates) with the roof down. Those are still quite fun to drive and often have hills and turns (unless we're in FL!). We go on two long trips a year right now, 700 miles one way and have a blast!
As for comfort, the 2015 (top trim line) is MUCH more comfortable than the 2008 sporty one was. My hips were always sore in that one after about two hours and the 2015 is just as comfy as my SUV, with, interestingly, a bit more legroom.
There is also a marked difference between the rag top (our 2008) and the hard top (the 2015) as for noise. The hard top is MUCH quieter on the interstates (for those rainy days when having the roof down isn't possible).
The Mustang you listed would be our next choice, if we wanted more room.