Whether you have many alts or just a few, do they know each other? Do they have some sort of relationship as people living in Azeroth, or is sending materials and money between them just a game mechanic for you? If your characters do know each other, what kind of relationships do they have, and how did those relationships come into being? If they don’t, what functions do your different alts serve?
I always try to make rp-backgrounds for my characters. I find it very difficult to actually really enjoy a character and level her (yes, I mostly play girl toons) if I don’t know her background. It would also make it easier for me to know how to respond if I would run into someone else who initiated some rp.
For my main character Orronil I always had in mind that the other nightelves I have as alts are her cousins. I knew she couldn’t have any siblings because that wouldn’t’ make sense for her background story. My hunter Ethelind was her cousin. Orronil tried to get the shy hunter into more social activities by dragging her to the inns and pubs, only to shove the girl to the nearest group of people and watch what would happen.
My draenai are all sisters. I have three at the moment: Yuvaraani, Rahiema and Salinual. Salinual is the eldest and a devout follower of the light. She’s serious and very motherly over her sisters. Yuvaraani is the bookworm. She loves to experiment with her magic and isn’t afraid to use her curves to get what she wants. I call her my spoiled princess. Then there is Rahiema. She is the tomboy. Like her sisters she can cast spells, but she like to beat the crap out of things a lot more. The way of the shaman called to her at a young age and she loves the world and the elements. This girl often gets in over her head and needs to be saved by her siblings.
If my characters are in the same guild and they are not related, I would just say that they know each other because they are in the same guild. They might be good friends or perhaps they only know each other’s names. I actually still want to make some friend-connections between my alts since I’ve only been writing family ties.
However, when it comes to sending mail I am very much the ‘my alt needs money and bags-type’. I really am far too impatient to write a letter to…myself