Hello. I don't have any advice, but am having similar thoughts so thought I'd chime in! I'm in the last year of my PhD and am doing a part-time consultancy job that I can continue/expand after my PhD. I also have no ambition to be a Professor - they all seem completely overworked and broken. But I do want to continue my research, and like you would be able to do that WFH. I know that people say you shouldn't do postdocs for too many years, but the idea of a grown up salary (compared to PhD stipend!) alongside freedom from teaching and admin seems like the dream to me.. I think my current ideal plan would be to do 2 days well paid consultancy, get funding for a 2 day a week post-doc and have 1 day buffer to do extra hours on either as needed. Have you considered something like that? I feel like it's easier to appreciate the joys of research when you aren't doing it full time! Would your current job let you go part time?

I'm a prof, and I spent 5 years as a postdoc about 15 years ago.

postdoc positions can vary radically between labs and disciplines. Some are highly competitive, long hours, others are more chilled. some are geared towards becoming an academic scientist, others have more interactions with industry / other roles etc.

if you aren't set on an academic career, i'd say treat postdocs like other jobs. So if you see an advert for the right job in the right location that uses your skills & lets you learn new stuff, then go for it. Similarly for both a postdoc and for an industry job.

The risk in postdoc jobs is that you get stuck in a very narrow specialisation where you can't get promoted up (no academic positions) and younger cheaper people out-compete you for other roles. So make sure that any postdoc you take has opportunities to get a range of skills / networking / links with industry etc. And then treat it like any other job.

I'm a postdoc and have been on and off for around 10 years (not entirely through choice).

The advantages are as you've described - flexible especially with young family, none of the teaching/admin/workload issues of the lecturer/professor route, a variety of often interesting projects, decent pay you can live on.

There are two big disadvantages to consider. The first is that you're looking at a succession of temporary roles so there's always a lack of security. Length of contracts depends on the area, but mine have ranged between 3 months to 3 years. There are usually a fair number of postdoc posts around (in my area at least) but far more limited when you don't want to move long distances or need it to fit with other posts. Parietal is right that postdocs vary a lot - and when you need your next job you can't always afford to be fussy. Your best bet is to find someone you work well with who is successful in getting a lot of grants and who will write you in as a named researcher - but then if it doesn't get funded you're back to square one.

The other disadvantage is that you are always dependent on someone else's project and someone else's way of doing things. Fresh out of your PhD this may not be important to you, but as you get more experienced, it can be frustrating as you have your own ideas about what to do and how to do it and you want more say over the work you do - some PIs are great at giving you independence, but others want things done strictly their way.

I'd agree with Parietal - consider it as a potential job from a range of academic and non-academic options rather than a restrictive career path. Also what you want now might not be what you want in 10 years time - think about building a variety of skills (management opportunities are particularly difficult to come by as a postdoc, but near-essential if you want to move out of academia).

Don't want to out myself by giving too much detail here, but if you'd like to discuss any of this in more detail, feel free to PM me.

Are there universities /departments /research institutions in your field which have strong links with industry and which focus on industry-funded work? These could be a good fit for you.
Also, work the other way: identify the big research-active businesses in your field and investigate who their research partners are. Then see what opportunities exist for how you want to work.