I gave softball hitting instruction for over 20 years. Worked with hundreds, maybe thousands of players.
I did it as a part time job, and for a time had my own business.
The tee is an essential part of fine tuning a softball swing, and being able to see live results when you take the tee to the field.
My advice would be to set yourself up with a profession softball hitting instructor (softball is much different then baseball or softball fast pitch) and take a few lessons so your swing can be evaluated and tips can be shared with you.
Or....Watch video of Ryan Harvey’s Tee work. He preaches what I “teaches”.
For seniors...Boggie and his videos are evolving in the right direction but...I would advice against his... past concept of low hands /uppercut approach.
Once you decide on your swing.. hang an old blanket off the corner inside your garage get a hitting partner and swing swing swing..then occasionally go out and test your swing offa tee on a field.
There is just one better tool for the money to work on your swing. If you have a place to hang some twine with a knotted up sock tired to it that allows it to swing out and come back to you to hit again..set it up.
I hung mine in two different places over the years..an unfinished garage and when i hit the sock it swung up into the wood garage door and swung back down to be hit again.. and under a high patio deck.
I would get hundreds of swings in at a time, usually with a light bat donut attached to my bat to increase strength.
But the best tee you can...Price should be no consideration. after all..the best tees cost less then half the price of a bat and will last much longer