I’m a practical planner – or at least I think I am – and the tools I use are important to my effectiveness. With that said, I do have a small obsession with using fine writing instruments, specifically fountain pens. I just posted a short video about a couple of pens I am using now.
The Lamy 2000 is a fantastic writer and I really enjoy it. The elegant simplicity of the design allows this pen to somewhat fly under the radar during daily use as it doesn’t immediately shout FOUNTAIN PEN! But the 14k gold nib is extremely smooth and the extra fine nib allows my writing to fit in the narrow lines of the planner.
The understated branding is also a bonus to this introvert as it doesn’t really draw attention to itself.
Another extra fine nib pen I use is the Lamy Studio. This metal bodied pen has a powder coated finish and a neat clip reminiscent of a propellor.
I also use a fine tipped gel pen – the Pentel EnerGel – with a 0.3 mm tip.
I also carry a mechanical pencil in my planner. The current model is a Pentel Graph Gear 1000 with 0.5 mm lead. The pencil sees primary use in the calendar and scheduling part of my planning.
I consider my daily notes to be part of my permanent record, so try to always use ink for those notes.
What pens or pencils do you use for planning?
paperinkplan 
Like you, I am a fan of the Fine or Extra Fine nib on my fountain pens. In my planner I tend to stick with a subdued ink – blue or blue-black or sometimes a brown of subtle purple – and have one pen inked with a nice bright red for underlining or writing things I want to stand out. In reasonably regular rotation, I have two Waterman Hemisphere pens, a Cross Century II, Lamy Safari and LX, and two Parker 51 pens. Love the two Lamys you have shown here.