Tell me, what should be the sole purpose of a thriller? To deliver 'thrills' right? Let me assure you, 'Blurr' has served its purpose just fine! If you consider yourself a fan of this particular genre, then rest assured, you're going to have plenty to enjoy.
Despite its flaws (which are strictly numbered BTW), as well as the fact that it's a Bollywood retelling of a well-known Spanish thriller (Julia's Eyes); I believe this would still appeal to a much wider set of audience just because of how neat and tidy the whole execution comes to be.
Be it the stunning picturization, or the minutely detailed background score; the technical sides are indeed remarkable. The story is borrowed, yes, but the creators still had the responsibility to safeguard the actual essence of the original screenplay, which they did. Albeit the pacing to me seemed a bit off at certain places, tighter editing might have yielded better results in my opinion.