Re: I'm worried switching to cloth at night will disrupt her sleep!
Sort of the opposite but possibly relevant...my dd1 was a rough sleeper, I had her in cloth at night. I experimented with sposies at night b/c I thought that maybe the bulk (just an organic flip in a bgos) was bothering her...but she did not sleep any better in sposies. I ended up switching back to cloth at night. She only started sleeping well at night when she potty trained (thankfully at 20 months) and figured out to hold her pee all night.
So, the moral of the story is that if she is a good sleeper the diaper probably won't make much of a difference.