Mayby you make one test server to classic zombie plague witch no extra items no zombie class ( only default zombie classes ) and all old classic maps ( i have all maps what was running in 2007-2010 )
Anyway, i see it will be best idea, no zombie servers anymore where to play ( all server got so many plugins and stuff its just not good. )
Almost forgot one thing: i can help you to build up this server ( just in case, if you want help
)