So many good things have been said about these pens that I can't add much without addressing their shortcomings. All three are very good pens, but they do have their flaws.

1990s faceted Namiki Vanishing Point
The faceted VP is a very good, but flawed, pen. It took less than two years of use before the matte black paint started to chip off, revealing the shiny black underbody. The pen still worked, but now it looks like it has been harshly abused. The VP's pushbutton design and relatively low price imply that it should be a good pen for daily use. If that is your plan, look for one of the shiny plastic pens. They may be more robust.

Rotring 600, second hexagonal version with smooth grip
When the paint started chipping off the VP, I didn't expect to find a good replacement. Oddly enough, the paper shop that sold me my first Moleskine notebook also carried Rotring pens. After watching the VP degrade quickly in my hands, a solid brass pen was very attractive. I took it home, filled it with ink, and have been tolerating its too-wide medium nib for five years. Unlike the Namiki, the Rotring has minimal signs of wear. There is some brassing from capping the pen, but nowhere else. I don't post the pen, so the end looks shiny and new.

Lamy 2000
Plenty has been written about this pen, all of it true. After five years of using the Rotring, I was worried that the L2K might be too light. Instead, I find the cigar shape makes it difficult to find a stable long term grip. The only other problem is that the pen is too short unposted. Both of these problems may go away as I become more familiar with the pen. For now, the L2K will be my new daily use pen.

Ink
Waterman Blue-Black
This might be the perfect ink, but the bottle could use work. You can tilt the bottle over to fill a long nibbed pen like the VP, but I'm always worried about spilling ink all over myself. The color and flow of this ink is nearly perfect.

Mont Blanc Blue-Black
Mont Blanc has the best bottle design, but their iron gall ink doesn't flow well in either the VP or the otherwise wet Rotring. When it flows well, I like the color. Both the Rotring and the VP write well once they've been cleaned and filled with Waterman ink again.

Lamy Blue
I have not tried this ink yet, but the bottle should make filling the VP easy. I prefer blue-black, but am reluctant to spend money on another iron gall ink after the MB experience.

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You should give the Lamy Studio a spin... it's a pretty durable pen, and has a nice-sized grip. The only downside (some wouldn't consider this a downside, though) is that it uses the same nib as the Safari, a pen that costs half the price. It's a bit on the dry side, but is a very reliable writer; it's one that I always know will never give me any trouble. Not very fussy about ink and actually looks better with age.

Seems like you're on that quest for the perfect pen (as are we all)... from your criticisms of each pen, the Studio might be more up your alley.

Update: I added a few photos. The DoF is too narrow on most of them, I may reshoot them with better light and a tripod later.

I'll keep the Studio in mind. Other reviewers suggest that the palladium edition's gold nib is similar to the L2K's nib.

The stainless steel Pilot MYU / Murex pens are interesting but they might be too thin. I'm tempted to pick up the most recent Capless but am worried about longevity.