If you hold your posted pen as light as a featherless baby bird, let the pen balances where it will.A longer capped pen(say a medium-long) will settle lower than a shorter Standard pen.
Metal of course will settle in lower..
There is absolutely nothing wrong with a fountain pen resting in the pit of the web of the thumb. There the web of the hand takes the weight of the pen taking away any 'un-balanced' feeling; or having to struggle with it if you are stubborn and insist it stay at 45 degrees no matter what..
One need not struggle to hold a pen at 45 degrees when it balances at 40 or when it is heavy enough to settle in the pit of the web of the thumb at 35 degrees..
Personally I like 'resin' pens over metal, but thought due to having a couple of the "heavy" metal pens, that if I do post it, will sit lower.
Will write fine from there too, it's just a matter of adjusting to the pen.
I have a Cross Townsend, a Lamy Persona and a Pelikan Celebry, and all three when posted rest in the pit of my thumb.
There are times when I just 'feel' like posting the heavier pens, for the sheer hell of it.
German vintage '50-70 semi-flex stubs and those in oblique give the real thing in On Demand line variation. Modern Oblique is a waste of money for a shadow of line variation. Being too lazy to Hunt for affordable vintage oblique pens, lets you 'hunt' for line variation instead of having it.
www.nibs.com/blog/nibster-writes/nibs-germany & https://www.peter-bo...cts/nib-systems,
The cheapest lessons are from those who learned expensive lessons. Ignorance is best for learning expensive lessons.