What if... you hold onto your lunchbox [no disrespect intended] until you find a good base model?
I liked my more recent rentals enough, but I was happy to be back in my Accord. I have not driven a Miata, though.
Is it that bad?
I would absolutely like to see a boattail, but if I ever found a Mirage that I could afford, I would loathe myself until I made one, but you already have the car, and the cheapest one that I can find is $3,900, although I saw it the last time that I looked, maybe a month or two ago.