I only had time to do two today.
Aliana Kae asked for "God Rest Ye Merry Gentlemen" in the style of Rachmaninov. I adapted the opening of the C# minor prelude and used the melody as a replacement bass line. I then played part of the melody in a Rachmaninov kind of texture and harmonic vocabulary.
Cynthia Gaitanis asked for a Phillip Glass "Go Tell it on the Mountain". I did my best. I don't know that style as well, and the cost of learning the style better is too high a price to pay.