I will use my own guild ideas as examples because I am trying to figure out the answers to questions such as what will it take to make this guild successful, is it even possible to make this concept successful, is the concept lore-abiding, and several more.
In-character, the <Disciples of Tush'ui> is a guild that presents itself as a school for those who desire a life apart from the ways of established society in Stormwind, Darnassus and Ironforge. Here, the masters of Pandaren monastic teachings meet to show Alliance citizens a new lifestyle of discipline and peace. For those who wish to take on a new challenge, the Disciples of Tush'ui can also learn to use meditation and the simple, everyday skills of life as a stepping stone to great strength, skill, and duty. Those of willing hearts can learn to become great protectors of their people and keep the peace which they so cherish, for themselves and for others.
Out of character, the <Disciples of Tush'ui> is an Alliance guild that is both casual-to-moderate role playing and casual-to-moderate PVP and PVE. Those who wish to just role play can be simple monks of our school who can gather around to hear the words of the old masters. But, for those who want to take it further, and want to be a part of the guild with their main character, we will be participating in casual PVP content such as battlegrounds and open world PVP and take part in PVE endeavors such as heroic dungeons, LFR groups, and possibly even combining our efforts with others for a truly hardcore raiding experience. Our motto is "Discipline, Honor, and Balance in all things." and we intend to honor the ways of Tush'ui.
OR
In-character, <The Long Path> is an organisation of people from all walks of life who have come together in a common desire to help their people. With the constant strife of conflict, war, and general upheaval among the nations of Azeroth, the fatigued, the weary, and the wounded are in need of a helping hand! We intend to provide that! Members of our organisation have devoted their lives to helping others in a vast array of ways, be it simply making guests at one of several of our inns feel comforted and welcome or be it offering therapeutic services to wounded soldiers returning from wars. Members of the Long Path have become experts at making the world seem not so terrible for those who have seen truly terrible things!
Out of character, <The Long Path> is a guild that offers spontaneous role playing experiences at several inns and quest hubs throughout the world of warcraft. Talking about your dangerous and great adventures while sipping a delicious cup of tea or relaxing your weary, wounded self in a steam bath with our friendly attendants are just some of the role playing opportunities we offer. AND, if you're feeling adventurous, we encourage you to get out there and spread good will among others, helping them with their personal quests and even following them into battle should you so choose! The possibilities are many here at <The Long Path>!
OR
In-character, the <Stormwind Craftsman's Union> is a foundation sponsored by the people, for the people, for the thousands of individuals out there looking to find the rarest and highest quality items, supplies, and materials in all of Azeroth! Here at the Stormwind Craftsman's Union, we take pride in offering premium services, craftsmanship, and materials for that aspiring craftsman. We are a collection of unique individuals who make it our job, nay our lives to find the rarest items in all the world and bring them to our valued customers in the great hub of commerce in the Alliance! Many among us are simply craftsmen who devote our time to perfecting our chosen skills while others are the lifeblood of our union! For those who want to experience the dangers of our world and claim the rewards from it, become one of our Gatherers! Join this elite caste of individuals who are responsible for acquiring most, if not all of our most valuable stock! Great profit and adventure awaits!
Out of character, the <Stormwind Craftsman's Union> is a unique hybrid RP-PVE guild devoted to monopolizing on people's desire to craft. This three-part guild features purely RP opportunities in our sales, diplomacy, and negotiations section in which you will use your shrewd business tact to sell our premium services and products to the people while also turning a profit for the guild, and for yourself! For those who want to actually take part in said premium services and products, use your crafting skills and part-time gathering skills to stock our shelves with inordinate amounts of valuable items and craft the best items for our customers who either do not wish to learn or have not yet learned to craft the items themselves! And for those who want more of a challenge, become a Gatherer! As a Gatherer you will be part of a group of people who's job it is to go out into the world and collect the rarest and most valuable commodities and deposit them into our stores. Why you ask? Because you will be rewarded with access to our crafting stores and a percentage of our overall profits, which will be stored securely within our vault in Stormwind Bank!
So those are 3 of my ideas. I have tried to find something for everyone within all 3 guilds and I do try to be reasonable with each theme. The first one requires only Monks as that is a part of the Tush'ui theme. The other two allow anyone to join but aren't as mechanically ambitious as the first one because they don't involve much, if any, raiding or PVP. I want to hear what you guys think. These are the kinds of theme guilds I am curious about and again, asking such questions as, are they viable, possible, and lore-abiding?
P.S. I'd also be happy to get into talks with you if you actually decide to take me up on any of these ideas as I will have multiple characters. I just can't put the time in to RUN more than two on an RP level, so be forewarned, I'd need help.