So I've seen a lot of people when talking about zombie AI and other stuff that TFP has done to "stop cheese bases from working", mainly about how TFP has changed the AI in a way where if you want to have a realistically fortified or bunker base it is highly un-viable as zombies just plow through the weakest route (instead of the fun old days where hordes would try plow straight towards you), now having toggle able AI to switch between fun and anti-cheese base may take a lot of effort (unless the AI is purely weight based and the weights are stored in a file and not hard-coded in the AI) so i wont go in to that much.
But why not just add new zombies, horde specific or not, for example spitters that instead of a normal projectile, spit one that produces gas that penetrates blocks and damages only players for area denial, or a zombie that charges directly towards the players location and on a block hit does large amounts of block damage (which would have more of a dangerous affect to cheese base supports than a big thick wall) or maybe even just by fixing spider zombies so they climb the posts and if they cant climb any higher due to hitting their head they attack forward (meaning they climb the post then start destroying it from the top) or maybe even have zombie meat-pile work so if too many zombies die on a specific path they try to get under the player, and if they can they tower up on each other and break the floor from under the player