The first one is a Meisterstuck model. So it seems more "normal" as a normal "cigar-shaped" fountain pen. But to write with a heavy brass-barreled pen, it does get tiring after you've written a long letter. And the design is meant to be very elaborate - making it more likely to be used for a special ceremony than for regular use.
If you look at French pens brands, almost all French pens are mostly brass-barreled. S.T. Dupont, Cartier, Waterman (Waterman is arguably American, but is now a Parisian brand), etc. This was the style of pen made by many French brands. So, they are by nature heavier than "resin" pens. But even regular users of French pens admit that it is more tiring to write with if one has to write a long letter.
Also, in the West, we write in long script. In the East, they write with characters. What's the difference? Long script means the pen stays on the paper and almost doesn't leave the paper for the entire word. In the East, a character requires the pen to be lifted off the paper multiple times to write a single character/word. Lifting a heavy pen and putting it back on the paper is more stressful than lifting a light pen. Thus, a brass bodied pen doesn't work well in the East even for short letters.
When I attend functions, I normally bring a fancy pen - with a broad nib which is useful for signing a guest book. But when I'm at home or recently I was in my hotel room writing thank you letters, I try to find a lighter pen if I have one nearby.