Your lo is old enough to hold her awake time for 4 hours at least. So a morning nap might be 9:30ish when she wakes before 6 am. If she's crabby or rubbing eyes by 830 or so you can give her a snack or change activities so she can hold on for another while. The snack can also buy you some extra nap time,since she won't wake hungry for lunch.
I found with my lo and other that i've seen that nap time could be extended if the awake time was exteneded and you put them down with a full tummy (that is, give her a yoghurt, crackers and cheese or some snack that includes protein). Another option would be moving to one nap, since your dd is at the age that lo's move to one nap, but if she still needs her two naps, that would be tricky. I'd try extending the awake times first so she can have 4 hours awake time but making sure she doesn't go to bed overtired by giving the snacks and keeping the activities before bed very low key (reading books etc).
When you say she refuses to follow a routine, you mean she won't go down for naps or refuses to eat when you offer her something? remember that you need to be very consistent with your desired routine for over a week to start seeing some positive changes, so you might expect her to protest a little and eventually she'll get used to it.
I'm leaving for eastern vacation for tomorrow, but ill be logged in today for another 3 hours or so. I'll try to check tomorrow morning.