Yep, diamond plates all the way ! I like the dmt continuous diamond plates but if you do lots of graving then a diamond lap would be the way to go
Theres lots to consider.. gravers come in all shapes n tips for all different reason just like wood chisels have lots of shapes. If you pick up a pro book on engraving, it can help you with some of the different basic shapes. Magnification also helps to see the graver and if youve got it the way you want it....or if its off side or if the tip is broke... sometimes a longer heel is nice for doing straight lines..
... heel is the bottom of graver... it sorta sets up how the graver planes through the steel ( its almost like riding a bicycle )
.. dont forget how youll hold the work piece ! It has to be solid, either in a heavy pitch bowl or a nice graver vise.
Youtube has alot of videos on engraving. ... it will blow your mind and your wallet