I’m currently taking a course in Japanese kana. My suggestion works for all courses, but I’ll use examples from the course I’m taking.
Let’s say I’m given the prompt け and the correct answer is “ke”, but I choose “ku” instead. Then I would like to be shown both of the following pieces of information:
1. け is read as "ke".
2. "ku" is the reading of both く and ク.
And if I’m given this prompt and asked to respond by typing in my answer, and I type “ky”, which is not the correct reading of any kana, then I would like to be told:
1. け is read as "ke".
2. "ky" is not the reading of any kana.
Right now, memrise only tells you the first piece of information, and I think it would be nice to be shown both side by side.