I'll comment on the evening EMH.
We went in January and the evening EMH were great. though a little crowded, especially at MK and EPCOT. AK was great and MGM just doesn't have enough to do.
Went again the first 2 weeks of May and OMG. MK and EPCOT were both as if the park never closed. Had to use fast pass and the standby lines for TT and SOARin were worse than during the day. AK again was still great. Got bored at MGM.
Going in July and will by ALL MEANS skip evening EMH. since we are staying at the BC, to do plan EPCOT evening EMH, but will be at Soarin' and TT during illuminations. There was a 60 minute wait for Soarin in May, so I can't imagine what it will be in July. Will plan to do other parks at night during MK and MGM evening EMH. (Won't be there during AK's evening EMH).
When we return in September, we will go to all of the EMH, since this is a slower time of year, the parks (MK) closes early to the public, this will be doeable.
October trip, that will be hit or miss. Will play it by ear.
One more trip planned for 4 nights early December--haven't decided yet about EMH.
Let me said that you will be surprised how little the park empty. Makes you look around and say, wow, all of these people are staying on property!