Fix the Bot's AI.
Either fix the AI or install a new one where the bots will come running to you as zombies instead of just looking at you, while this is a very minor detail it's thing to fix and improve the server when not many people are playing.

Replacing bots isn't an easy job.. however I think they need a bit of an update.

I've found a zombie server using E-bot module and the AI was pretty neat..
https://github.com/EfeDursun125/CS-EBOT

(check 1:45)