Apart from the obvious choice for opening batsman, Tamim that is, I don't think anyone can match Imrul Kayes in ODI. For test I think ZS has got the edge over Imrul. Anamul is in the pipeline to be the next partner of Tamim or at least I hope to see him there.
ZS never stretches his bottom hand. I'd love him to see stretching his powerful left hand like Shakib or Tamim. It's as though his left hand is tied to his waist from elbow upward. More often than not he gets out by top edging as a result. (MHO)
He makes me cringe every time I watch him live but he's good for the longer version. He can stay at the crease for a long time unlike Imrul Kayes.
ODI - IK
Test - ZS