Which would be the best “keyfile” for KeepassXC and/or Veracrypt?

I am a Mac user. I opened a keyfile generated by Veracrypt and one generated by KeepassXC. The texts in both of them were quite short. Which keyfile is best (i.e., most random and harder to break through): one generated by Veracrypt or one by KeepassXC?
OR: Is it best to create my own keyfile?: I can open a photo with TextEdit, copy and paste the gibberish that shows up in an empty TextEdit file, save and use that as my keyfile. Is that be better?

I also wonder if it is best to use another type of file (a .jpeg photo, maybe) as a keyfile. My thinking is: files generated by Veracrypt and KeepassXC may stand out (assuming someone broke through my device and started looking).

Would anyone recommend embedding a file in a picture (steganography) and use it as a keyfile instead? How can I do the embedding in Mac? I am familiar with Terminal.

Thank you in advance.