I've been remote for the bulk of the past decade. There is definitely an increase in opportunities. I decided to live close enough to a metro area that I could get an in-office job if needed. And I did for one year before going back to remote work. Your career progression probably is slower when remote, in particular if most of the company goes to an office, and in larger companies. You'll have the best shot at growth in smaller companies who are 100% remote. You also do limit your job options, so if you job goes south, you might feel a bit trapped without local options for on-site work.
Mental health varies based on your own preferences. Self-directed, organized introverts thrive. Less organized extroverts... not so much. Remote work isn't for everyone, but if you enjoyed it for 6 month stints, you'll probably enjoy it for longer.
As far a family balance, it can't be beat. You do need to define and stick to some boundaries, both for family to leave you alone to work, and to put work away and go spend time with family. Be flexible, though - don't commit to a 9-5 schedule, and don't fill all your days with meetings. Give yourself days when you can take a 2 hour lunch with the family, and then make it up after everyone else goes to bed. Don't feel bad stepping away from your desk to see what kids are up to for a few minutes. Make sure your boss appreciates the benefits of that flexibility, that they also benefit by letting you work at the times when you are more engaged and productive.
Overall, you take a bit of a hit in career growth, but gain family time. I believe it is worth the cost, but that ultimately is something everyone needs to decide for themselves.
