While I do agree with Rexy about custom assets being a vital part of TF2 mapping, my personal opinion about new models and materials is slightly different from his.
In my mind, a map that looks great, plays great, and utilises old assets in new ways will usually, if not always, be more appreciated than one which uses brand new materials. I guess that what I’m trying to say is if I manage to make something new and original from things that are dry and overused, I’ll be more proud of myself than if I were to make something with 100 megs of custom content. For this reason, whenever the subject of the next contest arises, I usually suggest 5CP or multistage A/D. Sure, there are many custom maps which fit into the aforementioned categories; during contests, however, entrants find as many ways to stand out from the others as possible, and what better way to stand out than to successfully revive an old gamemode/theme/asset list?
I realise that some (if not most) of you will disagree, but I’d like to see a contest based on the use of assets in a completely new and original way with as little custom content as possible.
tl;dr
quarry_rockpike.mdl contest go