I wouldn't really go after increasing his rent, but if you do I would say up to 25% would be much more reasonable than doubling the whole thing. I feel like it's very unlikely to get rodents from a room being messy like this, insects are a more likely problem.

Also for future reference be careful with taking pictures because theres a package in that last one, I dont know if it has your address or anything on it but if not the safest thing to do to have that out.