Man fuck this thread.
Anyway... yea I mean it'd be kinda cool if the guys actually got some good customization options though I guess not many need it. I feel you on the headband part. In fact the headband should be off in the first place and you should choose to put it on.
For Bayman, for some costumes you could toggle his beret on and off. Maybe different colors too but colors aren't that necessary. Red. Black. Green. Maybe Blue. Last but not lease, no beret. Nothing more, nothing less.
Hayabusa could have his ponytail and untied hair like from DOA3. Masks and maskless for all of his costumes alongside it, granted those costumes give room for that.
Hayate should have an option of a graphically updated version of his old hair. No one can deny that his hair is clearly different, than it was in DOA4. Same for Ein. I like both styles but I prefer DOA4.
Same as Busa for Brad (Minus the masks part).
Something I miss for Leifang is her long hair in DOA4. Yea the hair in that game had disgusting physics but I like how it fell over her shoulders a lot. I'd like more of that even if it means making the longer portion curve around more (I don't know how to really explain that idea better).
There's a lot more that could happen as well but most of what I wanted for the girls has been done already. I just wish TN would crack and work in a character customization system.