Jenniferklm suggested this over in another thread, and as I've seen lots of photo-heavy blogs, I figure it's a great idea that's worth amplifying:
Another improvement. I might suggest if I could that would be helpful for people like me who write fairly long blogs with a lot of photos, would be to have some indication that you have already posted a specific photo to a blog, like a tick mark by the photo in the upload list. The photos seem to upload in a random kind of order and I am scrolling up and down looking for particular ones and sometimes lose track of ones I have already put into a blog.
Since inserting a photo just adds the code for it to the textarea, I can imagine all kinds of hard to implement edge cases if you're trying to account for people then manually editing / deleting that code; but maybe all of that can just be forgotten about, with the feature just being a really lightweight "already clicked this" marking?
(N.B. I finally figured out why I'm so resistant to posting issues over at github - besides the whole being owned by Microsoft and thus being tracked/marketed if/when being active over there. It's offsite, out of sight and mind, and I really like that when I post something here in the forum, that gives everyone who's active on the forum the chance for an immediate look at it, with the ability to comment, chime in, etc. I wouldn't expect more than an absolutely tiny percentage of the people who read this to actively visit another site for the same, let alone one which is as techie-focused as github is.)