I know it has been changed recently, but I would love to see less posts on one page in a thread.
Sometimes it just loads very long, depending on the internet connection and other things like browser, device, thread content, etc. At home on my PC it is fine, we have a fast connection (150 mbit/sec), but at work, on the countryside, mobile it is sometimes too much. Especially the image boards are sometimes not usable for me, and due to loading I oversee images posted earlier, and see them then later and thought like 'wow I've missed something'.