This may sound odd but it's a thought I've had for a long time

As great as they are they don't have their own animated movie. They are Queens not Princesses, and their movies have no connection to falling in love with their 'prince' (if Im not mistaken). And finally being portrayed by actresses, Disney wouldn't make them really DP's because they'd have to pay the actress to use their image for quite some time. Much like why Giselle from Enchanted isn't a real DP, they would have to pay Amy Adams. It would be an interesting thing but in my opinion they simply don't meet the criteria.