I had a lot of opportunity to try things out in beta. My game plan was to create a lot of characters from the beginning, each to specialize in a different craft and help outfit each other. So far, I've built 6 of the allotted 8, with an eye to balancing between realms and classes. It's too soon to see how well this works, but I tried a similar strategy in SWTOR quite successfully. Here in ESO, that is one advantage of having a bank account that shares your whole account, even as I get frustrated with the limited space.
I made 8 characters mainly to reserve my favorite names, though I do have very rough builds in mind for them (two of each class). I made them all in the DC, but now that I know that your bank and guilds are all shared account-wide, I will probably remake some of them in the other factions for some variety.
I'm playing a tank Templar first. Currently sort of overwhelmed with the huge number of activities available, I find myself spending an hour on questing, crafting, or exploration before something else catches my attention.