I am personally "afraid" of white leather too but have finally succumbed. For me, I may or may not get a white birkin or kelly in the future but I have seen how they "age" and it's just not to my liking.
I bought an evelyne pm2 in clemence instead to satisfy my "craving" for a white H bag. It is relatively inexpensive compared to a kelly or a birkin and am willing to "risk" it getting dirty.
I have considered a picotin too but my concern is that the bag is "wide open" and I am often on foot and would hate to see my kelly wallet or bearn get "lifted"...
I have also considered bolides, but am concerned with handles getting dirty. I could put twillys on the handles but I figure that with an evelyne, I don't have to do that. What I do is I use different colored twillys to match my outfit when I use my evelyne to carry it shoulder-bag vs. messenger style.
I will post a photo to illustrate.
Good luck with your decision...