Well, I DO think one can make a reasonable shot at an expectation of returns on investment in any vocational pursuit. I'd say the outcome of a Comair pilot is a realistic expectation for most regional pilots. However, I don't think the level of income stability and job longevity the OP desires is a realistic expectation out of any regional job pursuit.

So to the OP. NO, I do not think you are being realistic in attempting to lock in the kind of long term quality of life and income durability you listed, by pursuing a regional job. If I were you I'd look at other vocational avenues and fly part time or recreationally. If you were a military retiree that could bypass the regionals altogether, or a career changer with a competitive history of income you could jump back to when the regional adventure ride ended, sure, I'd say expectations wouldn't nearly matter as much going in. But cold turkey at the age of 31? Hell no your expectations are not realistic. You're free to pursue your life as you wish, but the profile of income and QOL you listed is essentially the textbook archetype every single working stiff in this Country desires for themselves.

A regional job is a time building job, not one where you can attain a sustainable financial position to those levels. Touching that standard of living for a couple of years before imploding doesn't qualify as being able to say one has attained that standard of living either. Much like the military, regional jobs are "up or out". You can't park it in the regionals as a life plan you intend to keep for 30 years. And at your age, you cannot afford to end up in the "out" side of the equation in 10 years because a displacement forces you back to 1st year FO and effectively prices you out of the profession in your 40s. Good luck to you. Your desire to make a competitive living as a regional lifer is what broken dreams in the "pylet" profession are made of. Life ain't fair, et al. We all gotta grow up sometime though and make compromises.