Movies that have way too much stuff going on in them for their own good (too many central characters, various subplots, etc.) and suffers more or less heavily from it.

The first ones that comes to mind is several superhero movies, such as Spider-Man 3 (2007), Iron Man 2 (2010), The Amazing Spider-Man 2 (2014) and recently The Avengers: Age of Ultron (2015)

Glen or Glenda.

The Avengers: Age of Ultron had just the right amount of stuffing. For me, it's the best movie that I've seen this year so far.

This does perfectly describe Spider-Man 3. That film had it's moments and doesn't deserve some of the bashing but there's no doubt that it was overstuffed and suffered from too many cooks in the kitchen. A film being overly ambitious CAN hurt.

I see this coming with Batman V Superman. That movie is taking too many shortcuts and jamming too much in to it. Avengers could do it because they set all these characters up with there own solo films. BVS ran to the front of the line too fast.

i just watched age of ultron for the 2nd time.. and enjoyed it more than when i first saw it.... i think its pretty well done tbh.

Yep, Spider-Man 3 is a good example.