There are so many opinions here, and your question is quite broad. I would say, I would choose the Leitz Tele-Elmarit (Fat) version, the black Tele-Elmarit from the 80's, and that's it. The reason is, these are more affordable. If you go to Nikon or Canon designs, you will probably venture into Sonnar designs, which are a different rendering. More contrast, depth of field curvature is different - pleasing. The first Elmarit has medium contrast, but lower contrast wide open, so no. The latest Tele Elmarit is too expensive. High contrast, but expensive.
I like the Type 2 Summicron. It is great wide open for portraits. It's not a Sonnar type. Contrast is fine anything past 2.8. It's fine. Just heavy - and I get that.