Reading all the different advice available, I have come up with a plan for that day:
1) Take the Mears shuttle to Universal and arrive before park opening
2) Start at IoA
Maybe get a butterbeer...
3) Hop over to Universal Studios
without any certain order, those are the attractions, we want to see there:
Men in Black (from what I understand it is similar to TSMM)
Jaws (has been described to me as "Jungle Cruise with shark")
E.T. (from what I understand a dark ride)
Mummy (a coaster)
Simpsons (I think it is a simulator ride like Star Tours)
I also am really looking forward to checking out the scenery, I like the Hollywood architecture and from the pictures I have seen, I think some of it looks really interesting.
4) Lunch will be at whatever CS place we come across when we feel hungry
5) Hop back to IoA
attractions we want to see here:
Cat in the Hat (dark ride)
Spiderman (I think kind of a very advanced dark ride? At least it is considered one of the best themed rides in Orlando)
Hulk (coaster)
and then also the water rides:
Jurassic Park (flume ride)
Popye & Bluto's Blige-Rat Barges (raft ride, I love raft rides and this is supposed to be really good)
Dudley D-Right's Ripsaw Falls
after the water rides we expect to be soaked, so we will bring a change of clothes, planning to store them in a locker at the park entrance. So I think at some point after all the water rides, we will get changed into dry (and most likely also a bit nicer) clothes.
6) end the day at WWoHP
all reports say that WWoHP empties out in the last hours of park operation. So this is when we will do our exploring there and ride the rides:
Forbidden Journey (definitely want to get a second ride!)
Duelling Dragons (inverted coaster)
7) after the park has closed: Dinner at Tchoup Chop at Royal Pacific Resort.