:::: OK, so that's your terminology. Is it also the way the terminology is used in general? My impression is that the difference is more gradual and there is no objective (let alone quantifiable) cut-off point that makes evidence "suggestive" (for dominant hypotheses), "strong" (for theories), or "conclusive" (for facts; or however you term these steps). Also, the dichotomy between theory and fact you are advocating is rejected by our very own article Evolution as fact and theory. 
 ::::As for the Kurgan scenario, alternative proposals such as Renfrew's and Gamkrelidze & Ivanov's, let alone Out of India, suffer from so many serious difficulties that they seem unsurmountable, and the arguments originally adduced for them are not particularly compelling. The main weakness of Kurgan seems to be that it has possible problems too, but in no way are they equally serious drawbacks as those of its contenders.