Without EQing the bass as
@Trell noted, it's easy to understand your dilemma. The midrange looks good for the most part.
View attachment 71083
The physics of the connection to the ear canal of headphones, is still not clearly understood. One thing is certain that the FR of a headphone should not be a straight line. It is my understanding that Sennheiser use extensive listening tests to determine the optimal FR of their phones.
Because of the coupling between the auditory canal is going to be different from person to person, I think you have to listen to a variety of phones.
To me Senns usually come out on top. For me the listening experience of phones is significantly inferior to good speakers. The only phones I have ever heard that gives a good account of program are the Stax electrostatic phone. They are the world reference standard for headphones, but the cost a fortune, which you would expect given the complexity of design and manufacture.
This is a graph from Harmon in 2018 for headphones after listening tests.
This curve I think is different from the Senn reference curve. I have a strong suspicion that the variation in bass perception is the biggest area of difference between listeners. For me the Sennheiser suits me the best. I find the phones from others are too bass heavy for me as a rule.
Again, I would be interested to know what the OP has against speakers.