It's the mindset I'm referring to, not the ability to do the work or appreciate all the nuanced challenges and decision making that goes into it. There's a great book that's been out for a while called The E-Myth by Michael Gerber. It goes to the very heart of the issue of technicians who start their own business. Good read.
What I saw in the OP, and maybe I am jumping to a conclusion was a reactionary decision and a bit of trepidation when faced with projecting future business to finalize that decision. Step back and take the time to plan, forecast and then make a more informed, planned, decision. We've all been burned at one point or another when our business demands get ahead of us and we are being driven by the fear of missed opportunity. I'm sure there's a ton of stories to be told about that bad hire, POS equipment purchase or other business decisions made in the heat of the moment.
Define the role you seek to fill and the costs associated with it. You can do several scenarios, P/T, F/T employee or sub-contractor. Look at the revenues you are currently bringing in, what's on the books, and how much more you'll need to generate and how you'll do that, consistently. If they're seasonal, what will you do to entice them back or replace them in the next season?
In essence, it's about planning your future business based on your past performance, industry norms, market trends, and the realities of the labor market.
I originally started my own in 2008 while working for another company. I made a connection here to work as a subcontractor. That business grew until the owner was able to take it full time. Shortly after that, I joined him as an employee. He is not a tree guy and yet he grew the business because he surrounded himself with people who could fulfill the various roles, me being one of those, and respecting the talent each person brought to the table.
We have grown over those years to become a major player in our market and we continue to grow. The owner, while having gained knowledge of tree work and the ability to do it, understands that he is a business person first and foremost. That's the talent he brings to the table and we respect him for that.
Long way of saying, step back and take some time to do the planning or measure twice, cut once.
Good luck!