I don't have a Hellcat, but I thought about it extensively. I do have two other Challengers (2008 SRT and 2009 SRT), including one that I put a Kenne Bell supercharger on back in 2009, when that was still a pretty new mod for Challengers (also made it into a convertible, and painted it Plum Crazy, and some other mods).
The main thing I wanted to say to you was that if you haven't already done so, consider just a simple cold air intake and Predator tune, and maybe exhaust. This really does increase the enjoyment factor considerably. I was thinking about trading in my stock 2008 SRT a couple of years ago, and then just for kicks I invested under a grand into a CAI and Predator, and it is SO much more fun. Very good bang for the buck, in my opinion. Your Chally will never equal your GT, but those simple mods may rekindle your interest in your current car.
On the other hand, I doubt you'd regret getting a Hellcat. Just some food for thought. My 2 cents.