Kalank is a slow pacing, period drama which is typically Dharma in its approach but with extraordinarily brilliant and sincere acting by the cast. There might be some scenes which could have been done without but it's a story which stays with you. Special mention : Aditya Roy Kapur, Varun Dhawan and Alia Bhatt. Even Hiten, Sonakshi, Kunal and Madhuri are phenomenonal. This is an epic tearjerker and undoubtedly a nice film, even if not great. If you have been looking forward to watch Kalank, go ahead and do it for yourself without paying attention to the reviews. I did the same and wasn't at all disappointed. Who knows maybe even you may come to like it as well.
To me it's a 3.5-4/5 definitely. The reviews are pretty extreme and we can see a lot of bandwagon effect.