Your comparison btwn the 325is and the 325e is not wrong at all. Having owned both I agree completely: the 325e is much warmer, lusher and smoother than its predecessor. However considering your conditions, I think you'll have to spend days burning-in the 325e at first. They're ear-piercing at first, even to a guy with normal ears like me.
I have never tried the SR125e so I can't comment on that, but the SR225e is definitely even warmer than the 325e. However the sound of the SR225e is not as refined as on the 325e. If I had to choose only 1 Grado to be my everything headphones, I'd go with the SR325e.
when you posted, i was still editing my post. hehe. So i take it you tried sr225e and sr325e then?
So... just like how their I series counterpart, the 225-325 still retain it's generic progression?? As in, the sr225e is still less bright than sr325e?
if i had to choose only 1 grado i'd go with rs2e really, it's just a little too expensive at this time. And um, sr325e is seriously good. And since the price is ~mid-fi level, it has a great price-performance value too.