I don't think you are weird at all! Anything but flat is going to cause listener fatigue... I spent much time at Interval Research (Paul Allen's personal R&D lab) in the '90s on a team developing ways of taking audio to the next level. Part of that work was understanding psychacoustics. Our conclusion in a nutshell was: flat and no ringing. Really hard to do in a headphone, but doable. I have a pair of PMx2s, which do it. I am looking forward to hearing the Eikons, because it sounds like they might.
I might start an opinion war with this, but I must disagree. I have no acoustics research background, but I've been an audiophile for decades & listened to live music on countless occasions in more venues than I could list. I think Venture Guy has this backwards: audio gear designed to be flat pretty much guarantees listener fatigue.
Leaving aside studio-produced pop/electronic music (it's purpose-built & plays by different rules), live, unamplified or minimally amplified music performed in actual spaces is anything but flat. Its frequency varies greatly according to musical/instrumental content. For example, during a symphony, when the entire ensemble (incl. massed cellos & violas) develops a theme, one can feel pressure waves of bass & mid-bass...all those low frequencies emanating from larger instrument bodies really travel. There's much midrange & treble, but it sits atop on a foundation of dense, lower-pitch sound. Seconds later, things reverse as the violins take over--treble dominates.
Even if the ensemble could play at the same volume in dB over the entire frequency range, the character of the hall/venue/space would assert itself (the sum of dimensions of the room/space, materials used in construction, any sound reinforcement/attenuation devices used by designers), so that nothing is truly flat.
If one recorded the symphony just described--a digital recording equalized to be ruler-flat, then reproduced it on high-quality audio gear (speakers or headphones) also mercilessly engineered to be flat--the result would be inhuman. It would razor your ears off. Most of us have heard recordings and gear like this. Contrast this to the original live music, which rarely sounds "bright" in the way audio equipment owners know that term. On the contrary--it sounds rich, nuanced, and full.
This is one of many reasons that talented designers like Zach "voice" headphones & speakers based in their ears & audio/music experience. They become our avatars, bridging the gulf beween real-life music and reproduced music.
I become more interested in an audio product when I know its designer really exerted him/herself to voice it for optimal sound reproduction. Not to make it into an expensive equalizer, but to subtly nudge it in the direction of faithful reproduction, helping pull the listener through the chain of electronics to a reasonably good simulation of real music. That's very hard (and expensive) to do. But abdicating that responsibility by making everything flat is no answer, either. (thanks for listening)