> Tree felling
> I'm good at directional felling
imho, With or without insurance you should not drop trees around houses without using safety/anchor ropes. Myself, I use steel cables.
> trimming ... I won't get any jobs because my work is limited to 15ft.
I do not do trimming, when people call for just that I tell them I trim trees by dropping them and do it on the ground.
On the other hand, I have trimmed trees once I am on the job when the home owner has asked to have branches taken care of over the garage, over their roof, everything trimmed away from the gutters, etc. Some when they look around the new open space, then decide they want a few branches off this or that tree to open up their view more from a window or porch. Or ones hanging over a fence line.
Plus, pole saws make excellent brush clearers when you have to hack your way through wild roses (or whatever they are called).
You will not get trimming work if you do not have a pole saw. Now that you have it, use it :-)
If you have the cash, get the insurance. Just make plans to never use it.