It really depends on the look you want: maybe various letters could be a little off so it becomes an “I meant to do it this way” font, and that can be really good with the right words and sayings. But if you want to go strictly by the pattern for the rest of it, I’d start over with the E; it will stick out and bug you if it’s the only letter that doesn’t match up. I will recommend keeping the same number of blank spaces between each word, whatever you want to do with the individual letters.
You can just trim out the few stitches that don’t match the pattern rather than starting the whole letter over. However, there’s a risk of a) the little wisps of cut thread poking through as you re-stitch (more noticeable because it’s dark thread on light cloth), and b) the closest stitches that remain coming undone. Neither of these is the end of the world or the project, but good to be aware of.
I don’t know whether it was recommended to me or just my own habit, but I like to keep the cutting to a minimum and “un-weave” mistake stitches from the cloth, coaxing the stitches out with a dull needle starting from the cut stitch, and leaving a small tail of thread in the back (unless the whole thread is being removed).