Is it good to add new column in table WP_USER – Or – should I add stuff in metauser table?
I was questioning this because there is a WP function
/* Get full WP_User object instance. */
$user = new WP_User ($user->ID);
Will that work as well after adding column in WP_USER?
If you want custom fields to be added to your user, use the usermeta or create a new table with username as primary key. This would allow you to be future proof in terms of updates.