If I were forced to sum up my collection, I would have to say, "eclectic". I like all sorts of pens, especially those with unique filling systems or nibs. I tend to prefer modern pens, but have recently been branching out to buy some of the old classics. As far as ink goes, I am curious about most any "quality" ink; I don't want to harm my pens.
As a researcher, you are probably interested in the mechanics and engineering of fountain pens. If you haven't done so already, you should head to the Conid Pen Site, conidpen.com and look at the video of how they make them. Be warned, you will probably end up buying one, as I did, and then another . . . . They are a modern update of a classic Mont Blanc pen. I also really like the titanium nibs.
Best of luck with this interesting and useful hobby!
Being in the engineering fields, I research photonics (currently nonlinear effects in optical fibers), I have been drawn to a number of hobbies including fountain pens and more recently photography. Your right the underlying mechanics and designs are always interesting to me.
That site is dangerous, those are really nice pens.