CNC, thanks for the information. ANd yes, the order you list is correct.
The neostandard images are the ones listed on
this page. That page also gives details of how the ship sizes compare in size to the regular set.
The ++ standard was created by mlmbd to incorporate ships used in mods by PvK, Fyron and others. The only listing for it that I know of is
here, although many people seem to be making up their own naming conventions for the ++ images. It's all a bit vague really.
Finally, there is no + standard. I'm not sure where you got that from=-)