Currently leveling as shadowpriest and it works pretty good
Possible additions/fixes:
Dispersion on specific health option (only option to use it based on mana atm) as shadow
Archangel - Spell - World of Warcraft is only disc in MOP so no need for a shadow option.
Usage of Shadow word insanity (tier 3 talent)
Option for multi dotting ( shadow word pain and vampiric touch - vampiric touch is the source for mana atm so it will not be a mana problem at all)
Usage of vampiric embrace
Vampiric Embrace - Spell - World of Warcraft (coldown spell theese days) and a option to select at what %hp to use it.
Use of Mind Sear on AOE (option to setup how many mobs maybe)
The "use only mind flay on low mana" option needs to cast vampiric touch since its our mana generating spell. If that is up then there should be enough mana for the normal rotation.
It really rarely uses shadow fiend and dispersion even when below thoose mana values I specified.
It sometimes (rare) ends up putting up vampiric touch then doing 1x mind spike (which removes dot) and then again putting up vampiric touch - which is really dumb, but it happens really rare ( like 1/50 mobs) and I can't seem to figure pattern.
Basicly if the mob live more than around 10 seconds you want to have both vampiric touch and shadow word pain up. Also it should never cast mind flay without having any dots up, then it would be smarter to use mind spike.
I would like to say that it overall works really well and even a spell such as angeletic feather ( speed buff talent) works flawless (didnt pick it in the start since I thought it would never work anyway lol). Let me know if you get in doubt of when it should use the above mentioned abilities or more details of the requests.