I can't do it! I don't have a huge number of bags (8 BVs, but 6 are the same style in different colours, 3 Balenciagas, all the same style in different colours, and one LV). I love each and every one and each one has a role in my wardrobe. I feel like I would be betraying any of them that didn't make my top three - sort of like if someone asked me to rank my top three of my four beagles!
So I can't or won't name my "favourites", but I will rank the bags I use the most often (which is different - since it is objective not subjective and therefore none of the others will get hurt!):
1. Nero (black) Bottega Veneta Montaigne
2. Carmino (red) Bottega Veneta Montaigne
3. 2006 Black Balenciaga Box