When you have long tags in tag box it is very hard to go back to the first tag and edit, there is no option of having a slider in the tag box, which is making it very difficult to edit any tags if you have especially long tags as shown below. I always have to delete the tags and then start over.
My suggestion would be having a google like slider for tags where you can easily slide from left to right and edit if there is any wrong tag or mistake as shown below.
