Those seem like two somewhat distinct regions of definitionspace. But yes, they sound about right for what I usually mean by "open-ended". X-Com would be mostly an example of the latter, while a sandboxy game like Minecraft would primarily identify with the former.

But at this point I think it's more convenient to ditch "open-ended" and find other words to associate less confusingly with those notions. "sandboxy", above, is my first candidate. I have no good ideas for the other kind at the moment.