Say I want to review a list of verbs, and I create a deck of flashcards, with the polite form verb (よみます） on the front and the English infinitive (to read) on the back. Is it better to review by reading the English, and trying to recall what the Japanese is, or the other way around? I'm aware that you should do both, what I'm asking is whether it's better to do it one way or the other when you're first reviewing new vocabulary.
I assume you mean 'review' not 'revise'. Review which ever direction you are having more trouble with. For the most part, I found reviewing Japanese on the front the most useful. My goal was to be able to read Japanese, once you can read/understand Japanese you have a lot more options open to you for studying. Half my learning now is just reading manga and playing games hah.
If you hope to have conversational Japanese faster you really may have to study both directions.
To add, I found that just doing flash cards the regular way wasn't very useful, nothing stuck. So for each card I would come up with a sentence using the word, or write it down (writing practice is helpful regardless). Or come up with various games... make a sentence with the last 3 words all the time resulted in some fun phrases. Or have a general theme for the day and make sentences relevant to the theme.
Wanikani is in beta and seems to do a much better job than I ever could with flash cards. It's strictly "Japanese on front" in the context of your question though.
To answer your question, I think it's better to show yourself the English and try to come up with the Japanese. I've always found that slightly more challenging than the other way around.