Hi! Currently my favorite drawing tool is the 6.0mm blue pilot parallel pen bc it’s super versatile. It does thin line if you hold it at an angle and thick lines if you hold it flat so you can cover large areas, also bc the nib is somewhat like a rake, you can get cool textures when it’s slightly drier.
The only problem I have with the parallel pens is the ink, which looks fantastic btw, but isn’t waterproof at all and will bleed everywhere if you’re not careful.
Of course I still use my staple grey and tan rapidographs (0 and 3x0) for fineline deadline stuff. I also love Posca paint markers. They are the crayola of Japan and have opaque ink that doesn’t bleed and dries thick and solid on pretty much every medium.
In my ideal world… I’d be able to use pilot parallel pens with real waterproof ink or solid Posca paint marker ink.