I will be strictly speaking about the Takstar HI 2050 and Grado Sr125i here, since they are the only pairs I own from these brands. Also, I'm not an audiophile/expert by any mean, therefore you should take my opinion with a grain of salt. Grado indeed has a more pronounced mid and treble than the Takstar, but also grainier and more colored. The Takstar, while (slightly, just slightly) weaker/less forward mid than Grado, cleverly makes up for that shortcoming by displaying an airier, more spacious and more natural kind of sound, which is what I'm after.
Like I said, my experience is tiny, so pleade don't take my words so serious. Hope someone can input more valuable insights to help you clear out the confusion. It would be ideal if you can try the Grado and find out what sounds better to you.
Edit to address your edit LOL: I have tried the L-cush, it didn't bring any noticeable change of soundstage width to my ears; it did however increase mid and treble sharpness.