Well, you don't say whether your Nikkor is black or chrome...LOL. I had a black one years ago and foolishly sold it. Now I have the chrome version. The black version weighs less. I also have a 90mm Elmarit. For awhile I had a 90mm Elmar also, and even had the short (Visoflex II) mount for it. The Elmar was stolen and I got a small fortune for the quite rare short mount.
The Nikkor is sharp, offers the speed of f/2, and it's heavy as hell. The Elmarit's head comes off and fits the same Visoflex system universal focusing mount as the 135/4 Tele-Elmar and 65/3.5 Elmar lens heads. Best of all it takes 39mm filters, and I have quite a collection of those from color slide days. They also fit my 35 and 50mm 'crons.
I've never based the decision to keep both lenses on the way that they "draw" an image, but they serve two completely different functions for me.
Buying the new black lens for why? You have two great lenses. Choose one, keep both, or blow a bunch of money on a new toy? Take an antacid tablet for your GAS. Buy some film.
That sexy new black Elmarit will be going down in value as soon it becomes a used lens. Both the black and chrome versions of the Nikkor have developed a bit of a cult following of late and prices are steadily moving up.
As a final consideration, if our forum's own compulsive lens tester Raid were to shoot a roll with each of those three lenses, plus for good measure, with a few of the Canon 85's and both the fat and thin versions of the Tele-Elmarit, print them all 8x10 and randomly shuffle them into one pile, would any of us be able to look through the stack of prints and "name that lens"?