Performance issues in the reply/add note editor

I have noticed recently that when we have a ticket raised with a long initial email (this often happens when a customer forwards a chain of emails to us) the WYSIWYG editor for sending replies or adding notes performs very poorly.  This is particularly a problem in cases where the emails contain image attachments (one particular customer of ours uses many image attachments in their email footers - 5 images in each email, 2 of which are animated gifs)

It would be great to see the performance of that text area improved, but a couple of other things could also help:
1. Show only the first say 50 lines of the original email, and have a "More ..." link to load the rest if it is longer.  This would also make it easier to find the "Reply" button when dealing with long emails.
2. Have an option of not loading attached images unless requested.