No cooldowns! Whole crafting system is based on cooldowns. You don't need to put a lot of effort in order to get materials its just job for patient people. I've already posted my suggestion about that in other thread http://fodev.net/forum/index.php?topic=2464.0 .Imho system of "search -> reward" is better than "click -> wait" and I think with that system it would be easier to limit item numbers.
Search -> reward. Forces the player to search for stuff for 2 hours and as a reward, he gets an item. Click -> get item -> wait. Allows player to 1) Get item, 2) Do other stuff at the same time. So in the end he gets items and can get experience or talk with others in Hub.Please explain how it is easier to limit item numbers if they were hidden on maps.Remember that big factions will do everything they can to get an advantage, so they will enter the huge map in 10 people and will find items within a minute or two. Also, such huge maps with creatures mean that TB players are fucked.