Baldur

I like this activity points idea you bring up. Maybe, each time you complete a thread, you get Guild Members/2 activity points. So if you had 2 guild members in a thread, you got 1. If you had 4, you got 2. If you have six, you got 3.

These activity points could be used to purchase things based on what type of guild is registered.

Support/Crafting Guilds: Maybe you could buy bonuses to crafting, materials, prosperity buffs. Things that will help you craft more easily. In guild wars two, you used to be able to buy, say, day or week long buffs, and everyone in your guild who did that activity in the time limit, got the buff.

Scouting/Questing Guilds: Maybe a bonus to LD, maybe specifically to find dungeons, and/or scouting the labyrinth.

Frontline/Raid guilds: Maybe they could use activity points to buy a safeguard like effect, or get bonus Col or Mats for the number of guild members in a party in an event boss/floor boss fight?

What other types of guilds do you guys see?

We're talking about guild activities a lot, but we can't really have guild only events. Guild quests are an interesting idea because we could make them scale to be much more difficult, but I'm hesitant to make content exclusive for part of the population and not others. Maybe we could have some kind of a guild difficulty setting?

*is just spitballing ideas*

I'm probably going to implement some kind of bonus for completing threads with guild members, probably 3 or more guildies required, or something that increases with the number of guild members in the thread. I also like the idea of having a group v group tournament. I want to see more parties built around working together, rather than everyone having their own single tactic and just getting shoved into whatever group has room.

I do like the idea of guilds having their own levels, however, we have a limited number of things we can buff before it gets out of hand. One thing that is always tossed around is buffing damage, but that's dangerous, because we have to balance these fights and difficulties and having 15 different damage buffs makes that very difficult. So I would love ideas of buffs or rewards that don't directly impact DMG/ACC/EVA/MIT

Yes i completely agree with not having Global guild only events but those events could be used to help the overall player base. For example. We could have a event of Quest with newbies where the guild who guides the most (non guild member) newbies through some quest gets bonus guild funds or all players in those runs get bonus col or something. Pretty much make guilds do charity work. 

With levels, I was think like a guild at rank 1 could have 10 members and every rank increases the max members by x amount. Or, we can link this to that guild member thread where doing threads with your guild mates give bonus col and other things like that. Increasing guild rank would that bonus by a small amount. Or the guild quest could have a guild rank requirement. I think you should buff quality of life buffs like col, easier time finding mats, chance for bonus results for crafting, lowering the loot requirements for x amount of mobs a thread. Small things that dont break the game but are nice to have.

While there is not alot, There is one type of guild that you havent mention but we have.

Teaching & Tutoring/Newbie Helper guilds: Guilds that assist lower level players and or help prepare players for the front-lines. They can get bonus that help newbies out. 

As I red this suggestions, gw2 always on my mind. I loved, truly loved that game. Ideas from it:

Guild bounty: the guild hv one month to defeat X amounts of mini-bosses, increase with difficulty. You can only defeat 1 mini-boss per thread and each member can only participate in 1 of the threads. Also, a set number of members MUST be in each thread(maybe 3-4 or something) and those that joins must help to kill it (1dmg is also dmg)

Guild race: here the players must complete a small race with obstacles you have to roll for. Dont have this all worked out just yet.

Guild trek: Just like guild bounty but instead complete mini-dungeons where you roll every ten posts instead (or 5 with reveal). 

The idea also is that you have about a month to complete the missions. And each player can be a part of several missions in the same month. But only 1 thread/mission.