There's going to be little you can do to overcome all the issues you have. From 2-edge reception from a mountain ridge in the way, to all the trees, and stations in every direction.Here you go.
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All you can do is try EVERYTHING you can think of that's easy. My first suggestion, since you can't go higher, or going higher might be worse from the trees. Try going LOWER! That's right, higher isn't always better. You MIGHT be able to get a better signal UNDER the leaf canopy. That, and perhaps moving your antenna to a different location around the house.
My signal layers at my house, are at 15' intervals due to trees. You need to find where YOUR signal layer sits, and get your antenna in the middle of it.
As for a possibly "better" preamp that may help alleviate some of the signal issues, I would highly suggest the Televes 560383 preamp. I use one myself. It has FM and 5G filters, and AGC. It also independently adjusts UHF and VHF.
Televes Mast amplifier with BOSS-Tech and “F” Power Supply Unit - 1 input (560383) (IF buying from them, try promo code: WELCOME5 at checkout.)