Paddy, mate, sensational!
Absolutely brilliant work.
The only tip I can give is to keep going. Experience is now your best "teacher". Experience will ultimately give you the touch in handleing the pencils. Just don't smudge. Please. The paper's texture here gives the sketch a certain 'energy of movement'.
If you want, maybe keep sharpening the pencil to maintain its 'edge'. Rolling/rubbing the lead on fine sandpaper reduces the risk of breaking the lead. A black charcoal pencil will give you a non-shiny effect. It is as black as the inside of a cat.
ASOD candidate here, I reckon,
I'm overjoyed at the result! Really, really good. Keep at it.
I've added a pic of what I've done to an eyepiece to give me a grid pattern. The optic fiber was placed at the EPs focus/field stop, with epoxy glue.