Good afternoon, dear …?
We want something we can call you, so that we can avoid the sound of the typical corporate copy and rather write to you in a personal style. Whether you prefer just your first name or full name, want to add (legitimate or not) honorary titles, emojis or anything else, feel free, this is you we're talking about after all. You're awesome. Note that this is also used on the company member listing, so your team members will see it.
Apart from that (communication to you and your team members), this is never disclosed anywhere. Oh, and it can be changed as often as you'd like later, so there's no need to dwell on coming up with the perfect name right now. You've probably got something else you're supposed to be doing.