Fix the admin input to have numeric only with add and subtract button.
Put a damn user total in there so you don't have to guess how much to subtract or add on the admin site. (Easy way to to this is that you know how many point types there are from the main table and just loop a sum() in the sql. Icons may not be needed)
Put a warning admins shouldn't be doing this unless they want the extra work.
Get rid of the $wpdb->prefix and do it less programatically (I suppose we will call this work... deprogrammin)
Get rid of the stuff I commented out.
Install the better include system that i put in lb