I debated with myself quite a bit as to whether to go one B.net account or 5, like many here.

5 b.net accounts would allow me to use a single authenticator entry to log in on all 5 at once, which would be convenient but slightly less secure. I haven't set up my authenticator yet, I wanted to hget the bnet login stable first.

Biggest reason I went to 1 bnet account instead of 5 is just a hunch/wish. I foresee a time when Bind to Account becomes more global to your bnet account in terms of heirlooms. You can't do it today, but I just have a hunch/fervent wish that one day you will be able to share your heirlooms among your toons on the same bnet account, even if only on the same faction or server.

Which would be nice, as my main account has tons of shards and badges and such, but my RAF/alt accounts have squat at this time.

At the end of the day doing one account was also lazier, and I don't/won't run enough accounts to cap out the bnet account.