We took our then 2 1/2 year old in 2019 to DW for the first time and MK and EPCOT ended up being her favorite parks. In MK we started off riding all the rides she was tall enough to ride. After riding everything she could ride, we brought her to the Prince Charming Carrousel ride and we all took turns staying with her while the others went to ride the rides with taller height requirements. She ended up riding it at least 7 or 8 times and had the best time of her life doing so!!! The rides that were dark (Pirates, Peter Pan, etc.) My husband or I kept our arm around her so she would feel us next to her and she never got scared of the dark rides (didn't do Haunted Mansion).
We went to EPCOT (this was during F&G) and she fell in love with the character topiaries. We couldn't get to the rides because she was squealing over the topiaries, lol! Once we were able to get on rides, we realized how many rides in EPCOT she was actually able to ride because there were no height requirements. Again the dark rides we put an arm around her and she was fine. We happened to be at the right place at the right time because we were passing one of the countries (I forget which one) and out of nowhere, Donald Duck, Chip n Dale, Stitch, and Pluto all came out for meet and greets all in one place. This wasn't listed on the times guide but from what I've read Disney will do this periodically to help with crowd control.
We went to AK and she wasn't as impressed with it. She wasn't cranky just seemed bored. This was the only day she fell asleep in the stroller. We didn't do HS so I can't speak to that.