Analyzing Ether - Threatening to displace Bitcoin, I don't think so.
Ethereum Age: 2 Years. It was born on July 30, 2015. Bitcoin has been out there since January 2009.
Valuation of Ethereum: $34 billion, bitcoin collectively is $43 billion.
Growth: 4500% increase in the value of Ethereum since the start of this year. Bitcoin value has doubled in the same time frame.
Looking at this data, anyone can be sure that Ethereum would surpass Bitcoin in a matter of years and its worth investing in Ethereum at these low prices. Some predictions also say that July 2017 will see a fall in Ethereum rate to about $150, so I am guessing a $180 would be the best buy price. Apart from the investment being worth, I am betting that Bitcoin will still remain on top!
Other factors which gives a positive feel for Ethereum is the Bitcoin's scaling debate and network stability which seems poor at this time until the Segwit activation completes and is implemented. A fork would worsen the situation for a little longer term say 8-12 months.
Even if all these shows a positive signs for Ethereum to surpass Bitcoin and obtain the top position, I would consider the following points against Ethereum:
Despite a market cap that is almost on par with bitcoin, as a transactional currency, ethereum has not achieved much, if anything yet – I'm ignoring ICOs for now. I will consider that as part of its derived value.
Compared to the hundreds of thousands of online shops that accept bitcoin, ethereum is hardly used at all for online purchases, there is no merchant infrastructure, there are no payment providers like BitPay that I've found and I see little evidence it's used for remittance or other transactional purposes.
I’m also not convinced ethereum is well suited for this purpose. While bitcoin has an urgent scaling problem, making it currently less than ideal for (micro) transactions, the fix for this is relatively simple from a technological point of view – the problem is mostly political.
Despite hearing many claims to the contrary, ethereum with its vastly more complex blockchain, has a much bigger scaling problem than bitcoin, that is yet to be solved, even in theory. Concepts exist to address this problem ("sharding" etc), but those do not exist yet and may not even work.
So, in its current form, ethereum is not a viable alternative to bitcoin as a transactional currency, and it remains to be seen if it ever can be and will be.
As a store of wealth, ether faces even larger problems.
Due to its complexity and by allowing code to run inside the blockchain, it creates a lot of potential for bugs and opens up attack vectors. This has already caused at least five hard forks and one blockchain split.
Fundamental properties are still being worked on, not just from an implementation perspective but conceptually. For instance, it's currently unknown what the future inflation rate will be, or even how the network will be protected (whether via proof-of-work or proof-of-stake).
Everything seems to be in flux and under development. It's also difficult to trust a blockchain that has proven not to be immutable and rolls back transactions that are considered "unfair". All this just adds to the sense of uncertainty. For a store of wealth, nothing is more important than trust and predictability, and ethereum currently offers neither.
Even if these major issues get resolved and clarified eventually, I'm not convinced ethereum is even the right concept for a store of wealth. Intertwining store of value and such broad functionality in one complex, ever-changing blockchain, just doesn't make much sense to me.