You are going at a relatively low crowd level time, so you will probably be fine whether you do EMH days or not. At this time of year, more important than EMH is whether or not there is a MNSSHP at MK that night. If so, the MK gets VERY crowded in the late afternoon and closes early to non-party guests. So a bit of a bummer both ways.
Even at very low crowd times, you will need/want a FP for some rides. Toy Story Mania at DHS is a prime example. It is a slow moving, low capacity attraction and the wait times often exceed 60 minutes even at low crowd times. But I have seen Space Mountain have wait times of 5-10 minutes (basically walk on) at low crowd level times.
Beth, mom to older DD (8/01) and younger DD (10/06) and always missing Leah (4/22 - 5/1/05)