niharikabhol Until I get to your review on the queue list, my only suggestions are to read the Writing Guide (it's incomplete however), maybe read some of the reviews already done of other books, or study books that are popular on Webnovel or highly rated on Virtual Bookshelf.
Shivanyaa The magic word is review. But of course, queued.
AardwarkThe2nd Again, the review will be more in depth, and my suggestions before then would be the same as told to niharikabhol above.
Typically, the last remaining points in PD and CF are the successful conveyance of originality and depth as well as the balance of events and personality. RL is simply the level of writing in terms of language, phrasing, and sentence construction. I wouldn't focus too much on this point until the others are more solid.
As for a change in title, I'm not sure honestly. I saw how your story changed due to readers' comments/wishes. I can't say this is the best for plot structuring/direction, but it certainly gives a good idea of what people want. Time traveling could be in the title, and if you're going for a harem, that's always works in the title. Killing the protagonist is unique/uncommon, so keeping that could be a good point of difference.