You're not very familiar with modern fountain pens, are you? Most don't leak, and if you are really finicky about mess (like I used to be before children) you

You're not very familiar with modern fountain pens, are you? Most don't leak, and if you are really finicky about mess (like I used to be before children) you can fill them with a syringe... not a stray drop anywhere. The utility (and cost-effectiveness in many cases) of bottled inks, and avoiding the landfill waste of using cartridges is worth the extra effort in cleaning and maintaining a fine instrument.