Pros
Ascension offers good compensation compared, both in terms of salary and benefits. The organization is large, and sprawls over disparate regions of the US. That makes them friendlier than most to things like remote/virtual work for non-clinical positions, and offers opportunities for transfer or promotion even when your life changes. The organization is Catholic, and so is a welcoming space for many Christians.
Cons
Like many companies, your experience is going to be dependent on your management structure, and mine was very negative. Work-life balance was a myth, and a recent collapse in revenue led to deep cuts. When I started, my team was a skilled manager and 11 people. By the end it was 4 people and an over-promoted secretary. I routinely worked 60-70 hour weeks, and watched this place burn out employee after employee. It would have been manageable if there was some sort of relief valve, but middle and upper management were completely toxic. Cronyism was the rule, and power protected power at every level. I witnessed employees reduced to tears by their management, and also watched that same management laugh about it afterward. I left before the layoffs and hiring freeze started, but many of my friends were let go. The people let go were not the dregs, but rather anyone who had dared to voice dissent or disagreement with management. I would not work for Ascension again, nor would I recommend it to anyone I know.