AskHistorians

That's tough. I think if we're looking at it in terms of effects, Washington was the better president for the republican precedents he established, preventing the US from immediately turning into a republican dictatorship like many prior revolutions had turned out. Not every man has the strength to give up power, especially when he's wildly popular and praised (and Washington, despite displays of modesty and occasional desire for goddamn privacy, legitimately enjoyed the popularity and praise).

If we're looking at it in terms of ideals or what they actively worked towards during their presidency, I'd give the edge to Lincoln. While 'Honest Abe' is a bald-faced lie, as Lincoln was a shrewd political operator, it is exactly that flexibility which allowed him to adapt to changing circumstances and prepare progressive initiatives even before the public was ready to receive them. Plans are worthless but planning is invaluable, and all that. Lincoln was certainly not perfect by modern moral standards, but he was at the cutting edge of American progress, speaking by a national (Northern) average. As Marx called Lincoln, "The single-minded son of the working class"!