At the moment I like the Parker Cisele style pens, as they are quite tactile and, IMHO look great as a work pen - not too fancy and not too out of place in an engineering business environment. My main pen at the moment is a late 60s fine nib 75 Cisele fountain pen with Diamine Amazing Amethyst purple ink, obtained from Woofage's emporium. I'm actually using an old, rinsed out cartridge for holding the ink, which I refill with a syringe - that gives more capacity than the converters so I don't have to carry ink when I travel. It writes a little dry compared to the mid-70s Parker 61 I also use.
For a mechanical pencil I have a modern Sonnet Cisele, and store them with a ballpoint in a
three pen Conway Stewart case that also holds some credit cards. The
Leuchtturm pen loop was a recent discovery, which makes carrying a pen with a notebook or pad much easier.
I'm still trying to decide upon a good ballpoint to use. I'm using a fairly default choice - a plain stainless Parker Jotter, which is convenient as both kids have Jotters as school pens so we just need to keep a stock of one type of refill (except one prefers blue, the other black
). I'm tempted to get a matching Cisele, but I'm put off by the quality of the Parker refills - a disposable bic crystal feels far smoother to write with than a Parker refill.