Oak wilt is a devastating tree disease and very expensive to combat. There has not been any real improvement in the treatment and control options since the first product was released on the market back in the mid 90’s. For chemical treatment you have two injection techniques for administering the fungicide and for large scale control measures, trenching is the best option. The Texas Forest Service (TFS) publishes a brochure for managing oak wilt.
Racoons, squirrels, rats, you name it. If it can climb, it wants in your house. I frequently get called out to bid a tree trimming jobs where the only goal is to cut the tree back far enough so that wild life can’t use it to get on the roof. Take my recommendation and don’t butcher up your trees in an overzealous attempt to keep everything away from your roof. For starters, call a wildlife / rodent control service and consult with them. Arborists or tree trimmers are not the best people to talk to about controlling wildlife. I like to refer people to Austin Wildlife Pro.
To keep Raccoons out of your attic you only need a small amount of clearance. Raccoons are somewhat fat and clumsy; you won’t catch them doing many acrobatic tricks. I’ve watched a squirrel with my own two eyes scale a brick wall, so no amount of tree pruning is really going to solve that problem.