I have two kids and my childcare has run the gamut of home care with different children, homecare as the only child, daycare, etc. But, each of my kids was in a structured daycare center when they turned 2.5 and both of them just really blossomed in those classes. I think that that age is right when their minds are REALLY getting turned on. Plus, the structured daycares have a little bit more structure to the classroom and I think the kids thrive on structure. So, I think your daughter would really love the daycare with children her own age. The only caveat is - she might get sick more often for the first little while because there are more germs in that type of daycare environment.
BEFORE you make the change, really review the current daycare and see if you would be happy with your child there. Review the rules, regulations, how clean the daycare is, what would you do when they are "closed" (my daycare offers no childcare probably 6 days the whole year). Do they offer daycare around Christmas, etc. You need to be clear on all of that.
Good luck!
L.