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Have you looked on how they do it in Alloy?
You can either create a new project inside VS with it or look at the one on github
what exactly you are afraid of from bootstrap? if you use Bootstrapaware Content Area render - https://github.com/valdisiljuconoks/EPiBootstrapArea - (don't be afraid of package name - nowadays it has nothing in common with bootstrap, name is just a legacy leftover) package will give you pretty easy startup for getting your custom display options working (+tons of features on server side to control various life situations)
I am trying to implement EPiServer display options without bootstrap and I am not quit sure wich steps I need to to to get it to work.. I have managed to get the chooises avaible in the editor, but I am not getting to choise with me to the backend, anyone have an exemple on a simple way to implement this without bootstrap?