Quite simply, there should already be a system that anyone can access that lets us advertise parties we're forming for events (like dungeons, world bosses, etc). We all know that trying to find a party for anything is a disgusting waste of time, you expend more effort trying to find a group for a dungeon than you do running the dungeon itself.
Final Fantasy 14 has a system exactly what I'm proposing, its essentially a new menu that allows us to publicly advertise our group to the entire server.
for example i could title the group as "City of Ash 1 Veteran Farming Party"
I could set a CP minimum of 300 (meaning only those of 300cp or higher could join)
I can limit the party size if i wished to.
I can choose specific role types for each open spot in the party. For example: I'm running as a tank and i set three open spots, two classified as DPS and one classified as Healer.
in Final Fantasy 14 you are able to specify what classes you want for each role (like dragon knight as tank, warden as healer, etc), but since every class can play as tank, dps, or healer, that wouldn't really be a feasible option.
It would also be a huge help to separate the lists into categories such as: Ebonheart Pact dungeons. Aldermeri Dominion Dungeons, Daggerfall Covenant Dungeons, Trials, World Bosses, etc. This would help organize the party finder system and make it easy for players to find exactly what they are looking for.
overall a system like this would be far better than what we have (which is currently nothing). Having party advertisements listed all in one place would be a huge boon seeing as how we wouldn't be stuck in a single area advertising in zone chat.