A nib pen is neater. The marker type an be a bit chunky and can also fray at the edges after a while.
Another option is to get a bottle of ink and a dip pen, this opens up options regarding colours, the pens with the cartridges seem to only come in black or blue, but the advantage with the cartridge pens is there is a continuous flow of ink, for the dip pens, it's harder to control the flow of ink. Hope this helps
best of luck with it, the hand made touch is lovely