I hear what Mark is saying about finding a large company to become part of. Reg Coates said in a thread about his part in the Stein product development something like... its better to be a small part of something big, than a big part of something small.
Those things being said, it will depend a lot on your experience level at tree work, at business, and your available hours to devote to things. If you are looking for something invest your blood, sweat, and tears into, then business ownership could be up your alley. If you want to work 50 hours a week, you probably aren't looking at full time tree business ownership.
Some like/ have it both ways, in that they will work for themselves for part of the week, and someone else for part of the week.
For me, I have a wife with a stable government job that has insurance benefits that we can both buy. No matching funds on retirement though. Her stable salary, and my variable income help to buffer us through the hard times. We also benefit from wood products like firewood for our home, chips for landscaping, logs for landscaping, the business equipment to use at home for maintenance around the property, and specialty lumber, which can add up to some nice perks.
In the long term, I could see a municipal/ arboretum/ campus type job being great. I didn't have those options available to me, where and when I moved, and started my business. I hope to have the longer term ability to have a crew(s) do most/ all the on the ground work, and be able to jump in at will, and consult and manage the business.
It also would be great having someone else foot the bills, worry more about the headaches, dependability, hiring, etc. Insurance/ medical benefits/ sick leave/ paid vacation are great perks that are often only found with larger organizations.
Perks, I'm going to Northwest String Summit this summer. I asked myself, do I feel like having that weekend off? Yes. Okay. Decision made. Along with that decision, is that I will work the weekend before, that week, and come back and work the next week, and maybe the next weekend to make up for missed opportunities to meet with clients, maintain equipment, etc, etc.
Calling the shots is both good and bad. As the owner and principal climber, I won't be pushed to climb anything that I don't want. I can turn something away, or say we need X (rental lift, rental crane) to do it within my safety parameters. I don't really have to work with anyone I don't want to work with, and can keep the safety parameters where I want them.
Working for a small outfit will be less predictable, and less full time work than working for a larger, well-established business. And with that, there is less flexibility typically that with a small owner/ operator like myself. For example, one employee, at a last/late minute, needed to go to the Financial Aid Office for school. You would probably find it harder to ask off at the last minute with a more strict policy type company. I think his education is important to his long term success, and helping him out with this also will make him more flexible with me when things run long in a day, etc.
I think that in the end, some days are worth it, some days are not. In the long term, most tree workers don't make a career working for someone else until retirement age. Having a long term and short term plan are both important.