Is leaving worth it?

Hi all! I'm having a career dilemma that I'm not sure how to navigate.

I work for a great company (public university) as a UX researcher. I've been there for just over a year and it's been an amazing experience thus far. I'm a hybrid worker, but I can choose how often I want to be in the office. My schedule is pretty much my own and I can get all my work for an 8-hour day done in just a few. The networking has been great here and I've been able to beef up my resume/portfolio with cool projects since being here. I'm also taking advantage of the free tuition as an employee and going back to school for my master's.

My biggest issue is that the job pays like absolute trash. The salary amount I was told with my offer letter was great at the time, but 6 months into the job I noticed I was losing $1,000 a month to a state retirement fund I can't opt out of. Since I'm a state employee I have to pay into it and there's no adjusting the amount I pay. It's 12% of my salary every year (including any future promotions). The growth potential here is also very slow and linear with my next few pay increases already being predetermined. There's no room to negotiate a raise because again, state employee. I do, however, get paid that retirement fund money back if I want once I leave the job.

I've been applying and interviewing for jobs on and off for about 6 months, curious about how I stack up on the job market right now. Recently I just finished a third round interview for a research consulting company and I'm confident I will be extended the job offer. The only catch is that it's a contract position that only lasts 3 months with a strong possibility to be extended/renewed.

The department director I interviewed with did confirm that her company has had difficulties hiring contractors as full-time as W2 employees (the company recently merged with another, and laid off lots of folks because of it) but they have regularly extended contracts for those individuals to continue work. This contract job pays nearly double what I make now and its fully remote.

I don't know if accepting this contract is worth giving up a stable, easy job at the university currently work for. But taking this contract could dramatically change my quality of life in terms of pay as well as adding another great company to my resume/portfolio. Any advice or thoughts would be so helpful!