The advertise issue is a key, is not necessary to promote on Google or twitter (twitter could work tough) but at least to promote in sites related to crypto. Also do some intranet advertise among community's and dapps could work. But there is when I realized that every community/dapp advertise only his own material.
Proposals like the carried by @ocd understand this dilema by trying to boost new communities. Don't know why they not boost games (with delegations) but boosting new communities helps a lot.
Also is very hard to be informed on new contests, a calendar would help a lot