The 2 most significant reasons why i think this will not work out, are -
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I won’t be satisfied/fulfilled developing tools to enable folks to take undue risk / illogical strategies. Am not sure there are any potential clients if i state that i will develop custom trading tools ONLY if i agree with their strategy.
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Folks stuck in a scarcity mindset will cling on to their “secret strategy” with more fervor than their trading account password; and won’t discuss it with anyone, even to have a custom terminal developed for it/them.
IMHO, best bet remains to continue discussing/sharing ideas on forums like this, and maybe share some code or tools someday. Maybe the tech-oriented audience is on the API forum(s)? 
PS: If anyone reading this has any idea/strategy for which they would like to explore creating tools for themselves, please start a topic thread. There appear to be atleast a handful of folks on this forum already who can help create such tools or share an initial demo to get you started.