Naval ranks for capital ships, probably so. Has any thought been given to the possibility of Fleet Marines? There are controls for ground movement and pistols at least, and in boarding parties and repelling boarders, Marines would be of use.

I'm late to the party, so I apologize if this is common knowledge. I'll check the other posts and try to catch up.

To the everlasting glory of the infantry...

Owain ab Arawn
KGB Supreme Knight
King's High Council