Those trees are why the deer are there as others have said. The fact that you have trees to hang a stand in is a plus. Like the others have said just cut some lanes and don't alter the light edges in there anymore than necessary or better yet set up between there and their food source. The issue is really 2 fold. Getting a shot and making it. Getting into thick stuff is hard to do with out spooking every deer in the woods. Getting a shot in thick stuff is not as hard as you would think. Most people only find out when they have to make the shot and it never dawns on them to practise it before hand. How small of a hole do you need? How close can you come to a twig? How much would leaves defelct your shot? Why wait to find out. You'll be suprise at how small a hole you really need and be confident when the time comes.