Right now, you can use case formula for String, Number, and Boolean but it would be great to allow Date.
For example, I did a comparison between two date by subtracting them from each other to compare to columns of dates to determine which was the later date. In the next transform, I was to do a case where if DIFF is POSITIVE then select DATE 1 otherwise select DATE 2. This will allow me to do a comparison between two columns of dates