Most of my projects are donation projects now. Just because they are for donation doesn't mean anything really in terms of my approach or workmanship, more than once someone I know has fallen in love with something that I was just working on to have something to work on. So when ever the question comes up about what to do, the answer is you do whatever you would do for the person you most love in the world!
The guild my friends belong to have a preemie project for one of the local hospitals, and a "children's corner" which is household things of need/clothing for all ages, but my preferred design size is roughly queen.
The guild I used to belong to did Ronald McDonald House as their pet project. I don't know about now, but back then any other children in the family could also get a quilt of their own and I rather like that. I usually concentrated on "small twins" as we had plenty of lap blanket sized projects.
Currently I'm looking at a transitional housing shelter in my neighborhood, I haven't contacted them yet because right now I still have more tops than quilts. It's mostly for people leaving abusive (often substance fueled) households. Often they leave in the middle of the night at a very bad time in their lives with very little support, emotional or financial, and usually about zero possessions. The "shelter" is about a 1-2 year stay and is a secure apartment complex where basic life skills are taught along with a roof over their head and assistance in the various areas they may need help.
Foster kids have been mentioned, many needs and desires both with kids in the system and those aging out. Red Cross is another organization.
Different states have different rules for raffles, but another option is to make a fundraiser quilt for a group with a particular interest. I have fabric stored out for a cat quilt for the Humane Society for example. In my area (Washington State) raffles are harder than in others, and it would be sold at a black-tie auction.