commutes impact amount of time available for parenting. When i get emergency texts from friends who work in va and need help at school pick up because they are trapped in traffic - that tells me something about hard it is to manage a terrible commute and be a present parent.
Wapo had an article today about 90 min commutes being new normal in dc.
http://www.washingtonpost.com/local/washington-has-one-of-the-highest-levels-of-extreme-commutes-in-the-nation/2013/03/04/aee03892-850f-11e2-9d71-f0feafdd1394_story.html?hpid=z3 This is only going to get worse as time wears on.
We made a choice to be close in and live smaller - still single family home but small in awesome school district. it does not sound like op's budget provides that flexibility. if we had less money, in light of the quality of life issues, i would op for good schools over living space any day of the week.
Since OP's budget is decent but not great for the dc region, she might want to make a careful analysis on what parenting activities she or her spouse will be not be available for if the commute is one of those new normals of 90 minutes. every family has different needs but the optimism bias generally leads folks to underestimate the impact of a bad commute on quality of life.