Just some things I noticed quickly. Some kind of progress or status bar could be added when doing an import. I've imported a CSV I exported from Jira and it just seems to be continuously importing with no idea on the status of it (how long is left, is it even still importing or has something gone wrong?)

Also when using the select box for the "Field Type" in the field properties pop up, the list is going below my screen and I cannot see the bottom items in that list.