Adding the ability to view more than 20 users at once, preferably through a drop-down selector (20,50,100,500,1000) would make bulk edits of user permissions easier for administrators. Currently if you select a user and then navigate to the next page of 20 users, it does not allow you to retain the prior selected users, so all bulk edits either need to be performed against all users or a page of 20 users at a time if a lesser amount is needed. While lack of this feature does not significantly impact me as an administrator currently, I expect it to in the future as we expect our user base to expand.