No, the wingFlags value will be purged in the next release if it isn't already--it was new code put in with the best of intentions, but it went against the current system handling unique wing properties (dated spaghetti-code problem solving, I know). However, after review, the current system was revised a bit so that if we did want to change over to a neater system, it shouldn't be hard to convert old data into a new system.
I brought this issue up in a team meeting and it was decided that the old system will stay, at least for now.
To clarify, Mothrine wings used the "Wing Style" status effect and was the introductory point of when that method was used. The rationale at the time was that it was such a unicorn feature for wings that it didn't need a dedicated creature parameter to save (and possibly bloat saves for serialized NPC data). The same method was used for "Wing Position", "Horn Style", etc. These are invisible cosmetic status effects that track small values for unique body parts, usually being used only by the player character.
Now that wings and horns are becoming more than just a couple numbers (type and count), it would make sense to expand the creature parameters to support things like texture and color values (as well as position, etc). This kind of conversion did happen for "Uniball" and "Genital Slit", now under crotchFlags, and scrotumType, so maybe in the future if it is used often enough. But for now, we are going by the "if it ain't broke" philosophy.
