What if you never make it to a 121 Major at all in your career? Things change a lot. You might want to be at a 121 Major now, but what if you get an incredible offer that takes your flying career elsewhere. Because of this, I would pick the job that offers YOU the best qol in terms of pay, schedule and happiness.
You have a hard choice. I have had a lot of hard choices, but in the end it has worked out for me and I have no regrets. I hope the same happens for you.
Best of luck on which ever decision you make.