As the title says, I think it would be great if there was an option to hide the text-based post's thumbnails in compact view, while still showing them for other content (images, links etc.)
It would imho declutter the interface a bit and allow for better use of space (titles and a line or two of post’s text could then use this space more effectively).
It would pop-up the current comment (one that user long pressed) while adding to it also the parent comment on top. User could then when done interacting with it swipe it away (up/down) to return back to previous position.