The Alessandro are still Grados themselves. You could say that a blindfolded person can still tell that they follow the same signature. Of course the MS2e does not sound exactly like the 325e, but if there are such thing as "headphone twins", then the MS2e and the 325e are definitely such. Same goes for the RS1 and the MS Pro. The MS1 doesn't quite have a twin, but you could say that it's between the SR80 and the SR125.
Upon its upgrade to the e-series, the MS Pro has fall into the same pitfalls as it "twin" the RS1e. Grado took away too much trebles and hi-mids energy, resulting in a very "duddy" sound. I do believe that someone has post their impression of the MS Pro e, and it's not positive.
That said, a lot of Grado fans have reported that Grado has changed the RS1e series to improve the sound. However, no one seems to imply that the NEW RS1e is in the same league as the RS1i or the buttoned RS1. By extension, that includes the MS Pro as well. I owned both the MS Pro (i-series drivers) and the RS1i, and the MS Pro i could be considered the more linear, more neutral version of the RS1i. Depending on your taste the RS1i OR the MS Pro i could be better, but not by a huge margin.
It's not like they have different sound signature or belong to different "classes". I can say that the similarity between the MS Pro i and the RS2e is not as much as between the RS2e and the PS500e. IMO, all Alessandro follows the "Grado house sound" that is prevalent on the Prestige and Reference series, NOT SO MUCH on the GS, PS and GH lines.
Now as to why I recommend the GH1, you said:
For your consider, i need some improvements in depth, looking for more dynamics, need more smooth and sweet vocals, and also need better layering than my MS2e