Here's something I learned as just a member. For a guild to really work well all members should ideally be at least semi harmonious, if even if not always agreeing about things. Let's face it, we are all different, we won't always agree on everything. It's ok to disagree at times. But out and out unintentional or worse, deliberate dissension can break any guild, no matter the size. Members have to be able to get along. If they don't, your guild is just not gonna make it.
From an officer standpoint, while I haven't been an officer in a large guild very long at all, I have picked up a few important things. Being an officer isn't about the title, or the supposed power. It's about helping your guild work as a cohesive whole. It's about helping your fellow guildmates, and supporting your GM. It's not a power role. It's a supporting role. It's not being Batman. It's not even being Robin. It's being Alfred, back at home, making sure Batman and Robin have everything they need.
On your officers. They should be people you trust to run things while you are not there. People who will do the right thing. People who will tell you when something isn't right, and work to make it better. Don't constantly undermind or overrule them. They are your right hand men and women. Respect them, or you could end up with a very big problem. Know that sometimes they will come to you with things that you need to handle as GM, and you need to be willing to make the lousy call.
Being a GM isn't really about power. It's not about getting to be the boss. If you take the I'm your GM I'm the boss track, you will drive people away after a while. A good GM listens not only to their officers, but to their members in general. They are willing to take suggestions, and to make changes if someone comes up with a really good one. I've seen this in action. You know you've got a good GM when he pays attention to what all of his guild members say. Just making arbitrary rules to suit you isn't a great way to build a guild.
A solid guild isn't built on a million rules. I think We Are The Night has like 4. You have to be an adult, you have to ask to tp, you have to be willing to help and be helped, and you have to follow D rules. See, I'm just a GM, that's all. I tell my new guildmates, I am not your mother. I will not tell you what you can and can't do. I will not tell you what you can and cannot say in chat (hence being adults only). I am not here to hold your hand. I'm here have fun, and to help others have fun as well.
One last thing. Being a GM is, as some have said, a massive time commitment. Sure, there are times RL takes over all of us. That's the way it should be. Pirates is just a game. RL should come first. If you aren't in RL complications, you need to put in the time to be on. And not just hop on go AFK, or go off on your own little projects. An absentee GM is no GM at all. If you make a guild you need to be willing to see it through.
And that's my 2 (ok maybe 8 or 10) pieces of 8 for the day.