It's a decent song
Overall, I like your interpretation of the medley by making it a calm/peaceful song. I felt that at 0:56 you could have made the entrance of the brass instruments much louder so it doesn't sound like they are trying to hold back as much...
I also feel that you could have added a lot more to the song (It is a short song for a medley) so that you are slowly building up in the energy in the instruments and the melody and focusing even more on the main parts of the songs (maybe speeding up a little bit as well as making it louder).
A bit bland
I can't criticize your choice of songs since i'm a huge fan of the Kingdom Hearts soundtrack. The music wasn't irritating to the ear (I'm glad you didn't make some crappy techno remake.)
There were too many long-held notes in the background and it was taken too slowly. You tried to mix too many different melodies at once and didn't do justice to them individually. the harp in Dearly Beloved wasn't bad but the brass swelling whole notes mildly irritated me. Sanctuary was a bit too repetitive in the background structure and your approach was too generic.
Where was that third song in the medley that you couldn't name? I couldn't hear it. I only heard Sanctuary and Dearly Beloved.