O.K we all have seen BvS twice or thrice maybe (taking about Fans) but now lets discuss what could make this movie a bit better. I'm sharing just my opinion and requesting others to follow the same. Either read this article full or better to leave it and save your time.
1.Batman's Villain -: A batman villain with Lex Luthor
Villain of a particular character is nothing but its other side. A villain explains a hero a lot more than hero itself. As per considering the touch and tone of the movie i think "Riddler" suits best. He can incorporates simply by sharing information with Luthor. And I would like to choose Jesse as Riddler and Jaosn Isaacs as Lex luthor. (I heard rumors that Jesse was selected for riddler and Ridedler was in the script but later they merged Riddler's act with lex plan).
maybe some dressed like JOKeR
2.Rorschach's feel for Wayne's Murder-:
love the Wayne's Murder scene and it's the best ever presentation but also i would love some sort of "Rorschach" like narrations.
"We always like a dream where a society take care of each other (Wayne giving money to a homeless)......its a beautiful dream suits upon you after your eyes are closed" .
Ben Affleck wakes up and go for workout, There he completes the "murder scene thoughts" with further narration
"But reality is cruel, sometimes it takes time maybe a long time to accept that its all about force and the fear of force" ( Ended with joker's laugh and Robin's screaming). That's it and no one gonna question about Batman's brutality."
3.Superman need's Alfred
Superman- Henry Cavill is presented as a messiah for some and "A devil from the sky" for other's. This would be awesome if somehow Alfred talks upon how the perception of how people take different sides upon a single act while telling Bruce to stop. And can take a charge upon here that how "he's gonna divide people upon Superman because it's the survival for fittest and rule for strongest".
4.Lex and Amanda Waller
Love the Lex Luthor's plan to frame Superman and that's the beauty of this movie (Even better than Doomsday for me). Here i would love to see Amanda Waller and Lex Luthor discussing Metahumans fate in this world. Now this point will directly leave impact upon suicide squad. Director ZackSnyder should add some more horizons to Lex's plans and its impact.
5.Wonder Women at UN against Lex
Wonder Woman- Gal Gadot is just too perfect in this movie but i would love to see her being UN member or something like defending superman and opposing Lex over a debate upon Luthor's admiration to hold kryptonian technology. This may works well as the first scene of the Movie where Bruce is also there.
6.Defeat Doomsday but with Other Manner
Doomsday should be killed by using some tech for locking him and sending it to the phantom zone, not by using kryptonite spear. I loved the flash Cameo and would like him to be involved during the deciding moment with Doomsday fight where no one noticed anything accept a blur and Bruce recalls that dream/Cameo might not a dream.
7.Mythology of Doomsday
The creation of doomsday should involve some mythology and a Krypton's flashback. Like Jesse Eisenberg 2012 Encrypting Kryptonian ship's script and searches for Doomsday by holding it with the modern philosophical views like, "Even god need to be defeated and their's arises someone who can defeat to continue the cycle of right-wrong, Life-Death etc......some call him devil, I call him necessity to save god from becoming a Devil"
Lex "I know Why Superman is here, (smiles) to make me stronger than ever".
8.KGbeast Vs Batman
Love to see a better quality of goons than shown in movie because a person who can resurrect Doomsday deserves better solider around him. Or Callan Mulvey lost his hand in "Africa scene" and have a Gun during his fight with Batsy.
9.Perry White's Chat show.
Perry White- Laurence Fishburne should be the person Who's expressing his views over media on Superman and Batman. Also He should be a big supporter of Lex Luthor......considering him a hero for humanity after Africa's scene. Have Holly Hunter with the African spokesperson over the Discussion or the Special host, Hosting @Hollyhunter and Lex.
10.Amy Adams brings Aquaman.
Lois Lane AmyAdams should be the reason of Aquaman's Blured cameo saving her from drowning. (Aquaman don't want to get involved in Land's mess........he has seen the true colors of people......this reason is for the next movie).
I love the philosophical depth of the movie and i was unable to hold my tears at the last scene. I understand this Lex luthor is a different version than we have seen till now and i also love Jesse Eisenberg 2012 from the core of my heart ( awesome acting in The Double).