You'd be looking at fineliners then? Unless you're looking at putting down some fat lines on paper.
1.6mm ballpoints are so much nicer to write with than standard biros
The best ballpoints I've ever used (and what I use day to day) are space pens. They don't dry up, they don't break, ink lasts for ages (like the 1 in 100 biro that doesn't get an airlock) and write on anything.
The only problem is people steal them thinking they're not a £20 pen.
famously orange
Another ball point pen?

The only problem is people steal them thinking they're not a £20 pen. Having to explain to someone why you're really annoyed with them for nicking what is essentially is a biro means diligent pen pocketing, locking of drawers etc.
You can almost guarantee if someone "borrows" it, they're so nice to write with they'll steal it. And then deny it.