Great plugin but can be improved

Its a good plugin but while importing it should consider the existing username instead of ids.

For me, it assigned wrong email from importing csv to an existing user (admin) on the basis of user_id maybe.
it should also consider username while doing the import, so it only import/update the users by matching both id and username.

i hope it makes sense.

To recreate the issue, try to import some users to an existing site, you will notice, data shall be updates on the basis of user_id.