As far as Financial Aid - this is from the exit interview of the outgoing dean William Graham.
"we have developed unusually strong financial aid by Harvard standards. We support 90 percent or more of our students with at least half tuition and 70 percent of those with full tuition. Of those 70 percent, a number also receive stipends. I believe that 10 years ago, it was more like 30 percent of our students getting anything other than loans. We have been able to achieve this in part because we had good luck financially, and we managed to hang on to the same percentages through the economic crisis. We have not stepped back on our financial aid. It might be that we cannot sustain this forever, but I am hopeful that we can try.
A friend (MDiv) had full tuition and a 10K yearly stipend as a Harvard Presidential Scholar. She also mentioned that Harvard work study employment pays well - $17-18 an hour. They also fund summer programs, internships and travel.