I tried all different settings but the issue stays: When constructing solar blocks, some trees can stay standing right on the edge between the solar panels/accumulators. This is kinda weird and feels a bit cheaty considering trees' effect on pollution.
Can of course manually deconstruct the trees, but that's clunky.

Would it be possible to change something about how the character interacts with trees vs how solar panels do?

Unfortunately I can't do anything to prevent that by default, but one of the things you can do is make trees not collide with the player at all, which prevents the mod from changing their collision box. In the settings, all you have to do is enable the "Use remove collision lists" checkbox in the startup settings. By default, trees are the only things affected, and that should prevent it.

I think it's lovely, though it can make it difficult to see what I am doing. Easy workaround: clear the trees out before you build.