I'll take a different tack here: I'd be interested to know what kind of reasons you have for wanting to make the switch back.

I've been self-employed for 14 years, and the couple of times I've done this analysis I've been hard-pressed to come up with justification to get back in the employment "game". My personal situation sounds somewhat similar to yours. I started this venture single, w/ no kids, and relatively uncommitted outside of work. I've since gotten married, had a child, and picked up various and assorted commitments outside of work. If for no other reason I'm interested in your situation simply out of concern that I'm "missing something" in my analysis that self-employment remains the best gig.

I try to look at work, as much as possible, as a business transaction trading my time and energy for money. I've never looked at work as being particularly "fulfilling" or defining my person. I derive pleasure from a job well done and I enjoy feeling like I'm creating good value for my Customers, but my fundamental belief is that my work is just a means to an end.

I should be quick to point out I'm fairly lucky that, although it ebbs and flows, my current gig is generally not very stressful. There are bad days, to be sure, but in general I'm not at my wits end every day. I've also enjoyed the luxury of jettisoning clients who were undue sources of stress. Were stress a factor in my life I'm not sure how I'd factor it into analysis of a job. I'd want to know a lot about the "culture" of the prospective employer.

From a financial perspective I viciously normalized the prospective salary/benefits into an hourly rate number (erring, where I had to, on the side of making the job seem more attractive). I compared that to my current net income and logs of my hours actually spent working (I try to collect a lot of personal analytics). The two employment opportunities I looked at were a significant decrease in income per hour worked. (I recognize that I'm lucky this was the case.)

Even if it were a net positive to change back to employment I think I'd have had a lot of trouble ceding so much control of my life back to an employer for other reasons.

It's particularly bothersome to me that employers, at least in my locality (Midwest US), have almost no legal obligation to be "loyal" to me. They sit in a negotiating position that often allows them to demand unpaid overtime, uncompensated 24 x 7 availability, and silly contrivances like non-compete covenants. (I suppose if I were more credentialed, more of a "rockstar", or just better at "selling" myself this would be less of a problem, but I still consider an employee to be, effectively, a business w/ a single Customer. If that single Customer chooses to take their business elsewhere... That's not a position I could imagine being comfortable in.)

The idea of working in a corporate bureaucracy also grates to me. Perhaps it's just a matter of semantics, but coordinating my schedule with Customers to take a day off is exceedingly more palatable to me than "putting in a vacation request w/ HR" was back in the old job. Likewise, pulling an all-nighter or working a weekend "for myself" doesn't make me feel taken advantage-of like the same work did at the "old job".

Given that the time w/ my now 3/yo daughter has proven to be precious to me (more than I expected it would, for sure!) I can't help but think that I'd feel put-upon even more today than I did 14 years ago. It's difficult to think that any amount of money would make up that that, either.