I don't think it can be a combination of 1 and 2, they seem mutually exclusive to me.
A good store of value is typically something that goes up in value, or at the very least is not inflationary, so it's not something you want to spend. I could buy some things with my Bitcoin but I would never do that because I think it will be worth much more in the future.
So if Bitcoin (or anything really) is a good store of value then it's not a good currency, and vice versa.
I definitely think it will be either #2 or #3 for Bitcoin and some other cryptocurrency which is pegged to something like the dollar that could take off as a global currency. SBD are a great example of that.
I hope it's not #3 but I think that's definitely a possibility. At some point Bitcoin will reach a certain level of market saturation where there's not a whole lot of new money coming in. Your guess is as good as mine whether or not it will stay at that level or if there will be a mass exodus.
I should add that another reason I think #2 is much more likely than #1 is that Bitcoin as a store of value doesn't really threaten governments or banks very much, so they are much less likely to overly regulate it or shut it down. Becoming a currency obviously does threaten them much more so it will be much more difficult for any decentralized crypto to really crack that space.
My Reply to the statement "Bitcoin ... will be worth much more in the future.":
Yes, this is valid today. TODAY. ONLY TODAY.
Now Fast-forward in time some 30+ years, and imagine BTC is worth $2-3 MLN . Would you still (then) think "it will be worth much more in the future." ??? I think the answer is obvious.
As obvious is also another thing- the validity of such statement will slowly go away.
Not overnight, but day after day, YEAR AFTER YEAR, DECADE AFTER DECADE. Spending will grow, slowly, continuously. So will the level of acceptance, popularity, market saturation, etc etc.
List goes on and on.
Yes, at some point Bitcoin will stop going up in value, or will increase at a much slower pace. But by then (as you said it could take many years) another crypto (or even something else entirely) that is better suited and designed as a currency will have taken over that position, so Bitcoin will either remain a store of value or collapse.
Bitcoin apart from being a currency does not have much value added to it. Every crypt in future will be rising based on demand, and adoption. And demand ultimately drives adoption. However, apart from that one of the key that drives both demand and adoption is value like steem.
So I think, in future as you said, these newer crypt which have some value behind will rise, its only a matter of they being traded directly instead of in terms of BTC.