Personally, I'm not a fan of random length wire antennas. All the tuner is going to do is show the radio a good match. You could have a perfect match but a 100 foot long dummy load. There are a number of different companies that make good multi band wire antennas. All the antennas at my station are band specific and are so well tuned I don't need a tuner to transmit.
I understand you are just starting out, I would ask how the end of the antenna is attached to the support pulley in the tree. Is the wire through the pulley then tied to an attachment point or is it threaded through an insulator then a rope through the pulley to the attachment point? The wire is your radiating element and should be hanging in free space and not grounded.
How is the wire attached to the mast? It needs to be insulated there too.
How does it leave your house?
Do you have a RF ground? Usually, antennas have a radiating element and a ground plane (not trying t get too complicated here).