Where is the cream of the crop?
There's another guy that just posted a question similar to this one is I'll put something similar to what I told him. I just came out of 4 years of corporate to 121 regional about a year ago. You couldn't pay me enough to go back. 121 is pretty amazing life in my opinion that gives you time to do something outside work with no interruption.. Not sure why you'd lose your seniority to go scrub bugs, do accounting, mxx, mxx tracking, clean crappers, make drinks, load bags, flight planning. Unfortunately I was the fo that would do everything for a lazy capt that would just like to shoot the breeze with the pax while making their drinks. You do get to go to some neat places and do some neat things but your qol is pretty low outside of your job especially since you could be on call most of the time. You are single so that is you're only way you'll want to experience corporate as with a family it can be pretty tough. Plus flying with the same capt (which most in my experience in corporate are not very good compared to 121 guys I've flown with, who also have pretty dry personalities) gets old fast. With all that said I had one of the mid to lower end flight department jobs making decent money like the gentleman above me described. So that's just kinda a snapshot of what to expect. Hope it helps.
Best of luck with your decision,
Droops