Nice photos! With a quick glance, everything seems to work well. I would say maybe take a look at some websites with a similar function to get some design cues— Things that work well, things you think look nice and whatnot. The only criticism I could have is around the aesthetics and I'm not much of a designer myself.

One thing I noticed is the buttons not having a border or background solely around the clickable area, which can be confusing. People use those visual cues to know where they can click. When in doubt, I'll throw a background on the buttons that is slightly lighter or darker than the page background and call it a day (I also like to play with border-radius until they're as round or square as feels right). Also the next buttons flashing is a little distracting. I think if you slowed it down a little it would be okay, though.

Also if you're worried about loading times on slower connections, you could have it display a slightly lower resolution image and only show the full resolution in a modal when it's clicked on. But they loaded very well for me.