Heya,
I wouldn't call any of them "bass monsters." Simply emphasized bass, more than neutral. But hardly "monsters." That's internet exaggeration.
The 80ohm and 250ohm DT770 are essentially the same. They are the same headphone. One simply has more resistance applied at the voice coils to be used with higher voltage sources in studios or at home. They otherwise sound virtually the same, other than the interaction difference that the amplifiers have due to operating at different levels, one operates at higher voltage with the 250ohm, and one operates at lower voltage with the 80ohm. Any sonic difference will be due to that, and the amplifier is what is making that difference, if there even is one, not the headphone. So get which ever. Because frankly, they're the same.
Very best,