Talk to me about transitioning to a bed

We have had great success with our March baby in her crib so haven't felt the need to transition her to a bed. We are thinking of getting her a bed for her birthday in early March and doing the transition then. First of all because I guess she can't stay in a crib forever, and second because I'm hoping it will help with naptime/overnight potty training.

She stays so quietly in her crib until I go to get her at 8 am, then naps or rests quietly for her afternoon nap 1-4. I'm so afraid to turn these times into a fight to get her to stay in her bed/room. I don't want her to end up disturbing her baby brother's naps or to turn overnight sleep in our house into a nightmare! Thoughts?

Regarding potty training, she hasn't needed diapers during awake time since 14 months old, but she does her daily poop in her naptime diaper as well as pees quite a bit. She pees in her diaper quite a bit overnight as well. We do try to give her lots of opportunity to poop in the potty before naptime, but we aren't making much progress there. I'm thinking of just taking the diaper away once she gets a bed so she can hopefully take herself to the potty (with or without my assistance). Not sure how well that would work, but I'm out of ideas. Thoughts?

What other advice do you have about the transition to a bed?