So sorry but I do not think that VO will even consider the letter, the fact that the letter has to be edited by other forumers show that it is not credible in the view of the VO and he will not be able to consider your ability to use English efficiently based on this letter. Writting long letter to VO shows some desperation and does not make your profile look good. I think the only way is to study more, improve your language ability, take the IELTS and apply again, it is never too late if you really try and put in reasonable effort, there is no shortcut
