I didn't have any duplo with my first either and their ages are similar.
I got the pink set for DD1 just before she turned 4, and for exactly the reasons you stated it got put away.
Duplo is a great way to get them into following the more simple instructions, the pieces are easier to manage and snap together. Me, I'm all for independence. I have a 1yo too and the duplo is great for her even though she's had access to proper lego her whole moving life. The bigger kids have moved on a bit, but everytime their mates come over you can bet what gets pulled out, and DD1 is totally cool with helping the little ones build stuff.
Lego now also have a range that is aimed to the 3-5s....called.....nah can't remember but it's a new range and they do have some princess stuff in there.