For our family, we would definitely choose Ohana. We are a family of five and our boys are ages 4, 11 and 12. Three of us love a big breakfast and two of us do not, but we all love Ohana.
Here's why:
1) Atmosphere: Relaxed and quiet (we usually have the 7:30am ADR) with a beautiful view of the lagoon and the castle in the distance. It's extraordinarily peaceful for a character meal!
2) Family style service: The servers bring the food to you, rather than serving buffet style. This means we sit down, enjoy the view and talk - no getting up for food, juggling plates, etc. No worries about missing the characters and having to flag them down or wait for them to return to our table.
3) Food quality: Great pineapple bread, yummy juice, mickey waffles, bacon, eggs, sausage, fresh fruit, etc. It's all fresh and quite tasty (and I don't usually like breakfast.) There's something for everyone, and again, it all comes to the table.
4) Characters: Quality character interaction - they never seem rushed. Mickey, Lilo, Stitch and Pluto. Granted, I miss Minnie and I'm not a Stitch fan. But Lilo and Stitch really are a ton of fun - our boys love them - and we still see Mickey.
5) Service: It's always been friendly, quick and efficient at Ohana for breakfast- we make MK rope drop with no rush when we have a 7:30am ADR.
I can't say enough good things about Ohana breakfast. Chef Mickey's is a fun place and I sometimes recommend it for first-time guests because it's a classic - but given the choice between CM and Ohana, Ohana would be a clear choice for us.