GS Sailor Venus
I think it should be a choice. I hate how Gaia automatically makes a big change without confronting us beforehand. I like the rare chance where they give us a little freedom and let us decide.
But if that's the case, if they will make it optional, I wouldn't. I don't have any specific reasons why, I just wouldn't. They can't help but to make it a choice. After all, how would they know the same person is behind each mule account?
So long as they don't lock in your names as you change them (for example, one GS Sailor Moon can pass the name over to another user), then it would be fine, I guess.
I definitely don't want to use the friends list sharing function, because that would cause overcrowding. If you have a single account user as a friend, that person might be irritated at having seven or eight versions of you on their friends list (and it would need to be a mutual agreement to friend each and every account). And my Sailor Cronus account has six pages of friends, whereas I have other accounts with different friends. In a way, I feel that this organizes things a little. I'm a little more inclined to friend villains on my villain account, Sailor Scouts on my Sailor Scout accounts, and non-Senshi on my non-Senshi accounts. Not that I've made those exclusive, but still.
Plus, in the case of guild-specific mules (Sailor Donation-types), I'd leave those seperate as well.