I had the Benzes in that range (Glider L2, Wood M2, Ref 3) and enjoyed the heck out of them when I started in vinyl 10 years ago. But when I heard my first Koetsu, and its fat lush midrange, it was probably the biggest WOW moment I ever had in hifi. Definitely made the Benz sound like it had relatively scooped mids. Between the Benz and Koetsu, I also had some Ortofons; I really liked the Kontrapunkt "c" (very good mids) which has been succeeded in their line by the Cadenza Bronze (also very good).
I do remember the Benzes sounding somewhat like what you describe, though they should have a nice balanced sound overall, so it's hard to tell if the midrange thinness you're hearing is much more than it should be due to setup, arm match, phono stage match, a combination of all these factors etc. At the time I had Benz, I didn't experiment too much with phono stages and arms; I used a Benz PP-1 (with some loading plugs) and Fidelity Research FR64fx, the latter of which is better optimized for lower compliance cartridges. Keep plugging away and trying various setup tweaks. Vinyl is a long journey of experimentation and learning.