HTC guys,
After looking at the skin files, it appears to me that it might be possible to allow a limited amount of individualized personal aircraft insignia for all AHII players. This is because it appears that the game's graphics infrastructure allows small overlaid JPEG files for such things as insignia, etc., which appear to require 100 bytes or less for each.
For example, AHII could allow each player personal artwork for a single favorite plane. This artwork would be viewable by all players during the game, in the same manner as the 15-skins-per-plane currently proposed. Personal artwork might include a fuselage letter/number/symbol JPEG, personal insignia JPEG (picture of half-naked female with name, etc.), and a kill markings JPEG. Interested players would submit these to HTC periodically (once per campaign?) and they would be combined into an appropriate file format which would be downloaded for each campaign, and stored on the client PC in a manner similar to the different terrain files. 500 bytes per player x 5000 players = 2.5 MB for this hypthetical file. If the client software is able to determine who is in a particular plane, it could overlay the basic skin with these personal insignia, making each player individually recognizable.
Even if you could only do this for one favorite plane per campaign (to keep overall file size down) the concept is still appealing.