Everyone complains about the DC controller but it's actually really comfortable to me. Regardless if you want to add a DC to your collection, try this:
https://www.amazon.com/Retro-Fighters-StrikerDC-Dreamcast-Controller-Sega/dp/B0891L7RYY
That's a GDEMU drive replacement. It plugs into the connector that the GD-ROM drive would normally connect to. Mine is a clone of the original that I got on amazon. https://www.amazon.com/gp/product/B07G11VW1Z/
The white part around it is a 3D printed enclosure. https://www.thingiverse.com/thing:1585333
Edit: If you do go with a clone route for GDEMU, don't update the firmware. Just leave it. It works.
I heard mixed reviews too, like "don't update the firmware" kind of things, but mine already has the most recent version and doesn't really need updated. The only thing I've seen is a couple random freezes, but that's probably to be expected with devices like this.
https://www.amazon.com/dp/B07G11VW1Z
^This is the one I bought.
https://assemblergames.com/threads/req-dreamcast-archive.53514/page-6
Scroll down to the bottom for the links. I use JDownloader to grab the files. Basically you install JDownloader, then copy the Google Drive or Mega links, and JDownloader will automatically pull and assemble the list of files to be downloaded. From there you just pick and choose which you want.