I totally agree with that idea as I said in small conversation we had before about it.
Besides all you stated, There are capture and other options which people can use to destroy other people's farms.
Allowing it back, even one who started today could build his own farm server and take down[or at least be able to try] the high ranks.
Maybe if you inputted the limit, I can add something.
When you buy new server, you can choose whether it'll be repository or farm.Repository server will have very small limit of viruses which can be installed. Farming one will be unlimited, but on the other hand, farming servers will be a good pvp mission priority, and the more viruses you have installed there, the higher the chance that some1 will get IP of your farming server.