There are many posts on what the next lock box will be so I'd like to put for my own proposal!
The "Top Secret" Lock Box
This will have a chance at a unique ship dependent on your faction. If FED then SECTION 31 styled vessel If kdf… then whatever their secret organization is. I'm sure the klinks have an equivalent organization
If this were to bare fruit I would have to agree it will be odd that there would be thousands of top secret boxes dropping everywhere, lol. But then again so are the rest of the lock boxes :p
This would have a small benefit of the faction designation matching. As someone stated in a post somewhere "no self-respecting Klingon would use a Ferengi ship as their flagship or have the KDF designation. Their honor would be at stake if not killed on site..." lol And no FED would dare distort the image of United Federation of Planets by allowing any other vessel other then FED-designed ones to symbolize them let alone sport the U.S.S. designation.