I just finished found through the takeout process for photos last night. 39 2GB archives. Request took a couple of days to process, then I got an email with a bunch of links that they said were good for 7 days. I planned to load them into my Synology download manager, but the takeout system seems to rely heavily on browser state, so Synology couldn't download them. Each took 5 minutes to download at home over WiFi, and the takeout interface demands authentication every 10 minutes. It also reloads the page and reset my position in the download list on every click.
I've uploaded and expanded about half the archives on my Synology, and it's currently indexing everything, so I can't comment on the photo issues you've mentioned quite yet.
Overall, I'm happy there exists a mechanism to get my photos, but the quality of the experience is truly awful.