I think the two biggest success factors for steem are first it's speed. You have to be able to accomplish a lot of transactions fast and steem fits that bill. I think this is one of many downsides to bitcoin. It is just to slow
Second I think the fact that steem has no transaction fees is a game changer. If you have ever tried to send money you quickly realize it takes along time and it is very expensive. Steem is fast and free.

I agree the possibility are endless. I cannot wait to see what the future has in store.