Been there, done that, lol. You will be back
Quite possibly! I love GTI's and would gladly own another.
Best way to do it financially is have your muscle car as a second car and keep it for a long time. The amount of money you will drop on mpg alone a month as daily makes it a cheaper option in long run to just keep the gti and have a second car like this. People often don’t look at it this way until you have had a car like that as daily and you learn, plus the gti is more comfortable for a commute.
I can always look at a more 'commuter friendly' DD once the SPS is paid for in a few years. I totally understand your logic, though, and it weighed greatly in my final decision. Some lessons are best learned the hard way! Still, the ultimate factor is if I'm happy (which I am). If that ever changes, I can always find another automotive solution!