This is your answer, Don't use minecraft forge 9.11.1.965 because it's under development. Only like Optifine, Shader, TMI because there don't use minecraft forge. Try to use minecraft forge 9.11.1.953 because all mod only reach to this forge.
Secondly, If your mod is outdated especially big mods. I'll unable say anything about that depending on the person who created the mod.
Hope this help you in your minecraft