Mostly, these ideas are DarkLock and JohnLock centered, so very emotional and angsty and all...
1. You Machine!
Sherlock /is/ in fact an automaton disguised as a human being and manages to fall in love with John.
2-3. Wild Target (basically the same thing but two choices)
Version 2. John is really a hit man hired to kill Sherlock but ends up falling in love with him.
Version 3. John becomes a hit man after Reich, is unknowingly hired by Sebastian Moran to track a spy by the name of Siegerson, who is /really/ Sherlock.
5-6. Jekyll and Hyde
Version 1, 2 choices. After experimenting on himself to prove that either A. Baskerville holds much darker secrets than it seems to or B. Moriarty could have actually been a good person if it weren't for his evil genetics, Sherlock splits into two personalities.
Version 2. What happened during Reich was so devestating to John that /he/ splits into two personalities.
7. Nightmare State
After Reich, John is cascaded with nightmares which he is trapped in and can't escape/wake up from.
8. Frankenstein, 3 choices
Tired of being alone and not truly loved by anyone, Sherlock creates a creature who he names John and A. John falls in love with Sherlock, who denies his existence B. Sherlock falls in love with John but John is incapable of loving him back or C. They both fall in love with each other.
Thank you for your time, much appreciated, apologies for all the feels in these, and if these are meant for fanfiction only, I shall happily write them and put up the links for those who would be interested!