My only experiences with Studio Ghibli up to this point have been with Miyazaki's films, so I picked one at random, and this is what I got.
Ocean Waves is very realistic. It's a story about normal people living their normal lives. It's focused on problems that seem very petty compared to most anime, whose plots contain sweeping melodrama and constant twists and turns, and thus is rather more relatable, for what that's worth. Adding to the realism are things that wouldn't normally be included in an anime (a girl mentions her period, there's a brief scene of a few of the teenaged characters drinking), as well as complicated emotions that are hard to portray. One of the more impressive plot points (to me) took place in the school. Countless anime take place in Japanese schools, and almost all of them take their drama from the interactions between students. Ocean Waves did this for the most part, but also included conflict between the students and the school itself- the administration and how the school was being run.
Ocean Waves also manages to be one of the slowest-paced things I've ever watched. Which isn't really my thing.
Passable. It's obviously made by Ghibli, but as a made for television movie, instead of one that was shown in theaters, it had a noticably smaller budget. The designs are atractive enough, and the animation of the movements are alright, there just aren't that many movements to animate, and a marked over-reliance on still shots.
If you played the soundtrack from this film back to me, I probably wouldn't recognize it. The music had very little presence.
Like the story, the characters were very realistic. They aren't exciting, they probably won't make it on your list of favorite characters, but their personalities and how they interact with each other and react to situations was very realistic.