Um...it's pretty easy actually to see two of the shows without any rush at all.
You can actually three of the nightly shows (just not Fantasmic) with very little rushing.
All you need is a room at CR (the Contemporary) on CL with a Bay Lake view. Go to the lounge for the MK fireworks.
If you go to WDW with extended family, or get firendly with another family on the other side of the reosrt- you can could also get one room witha MK view and one room with a Bay Lake view. you could also watcth at least one show form one of the obvservation areas. The view of Illuminations isn't perect, but you can see much of it, especiallly if you are on one of the higher floors.
I'm guessing parts of BLT actually have an even better view, but I've never been in those rooms. i woudl think the BLT lounge has a pretty good view of both shows.
I know we've also been someplace else at WDW and seen at least partial views of both shows....I just can't think of where it was. Maybe out on one of the lakes. Agian, you don't get a complete view of both, but I kow there have been times when I cold see both shows goiing off at once.
Oh - the 3rd nighttime show you can see at CR is the water parade.
Sometimes we have been able to get from Epcot to a late showing of Wishes. OTehr tiems we've goteen stuck on the monorail. soemtimes you an see wishes from the monorail, soetimes you can't. The monorail stops during the show. Usually wit no view. you still get emh though!
I'm not so big on Fanstasmic! We've not tried to fit that one in too. Maybe if F! was early and you coul dget back to CR...
Oh, you can also get a room at the Swan with a view of Illuminations- so you could maybe do that combo.