So you guys that have a lot of experience with the Beyer DT range are pretty confident that the sound I'm experiencing is just par for the course for their stock sound
Yup. heard T1, DT880, DT770, T90, T70p and I can't bear them. The peaky treble makes my ear bleed. It't the only brand that make me that effect. I even can bear most Ultrasone treble and i've not much trouble with the HD800 treble. I think it's not only a matter of treble quantity . all Beyers present a kind of metallic ( think to the sound when we crumple an aluminium foil) sound I really can't stand.
Sell it and grab a Sennheiser HD558/598 if you can't fund a proper HD600 system. Fidelio X1 is a very good options for a more fun signature
For measurements, I personaly prefer to see raw measurements. i've my doubt about compensations curves. My listening impressions differ a bit too often from what I read on graphs.