Because of the various and specialized senses of the term "value" I think it is helpfully clarifying to say instead that you consider btc to be overbought in the near term.  In this way I hope to avoid confusion between distinct concepts with differing relationships to price.

Regarding a 1.000.000 usd exponential trend price in 2017, I think our intuitions are a poor guide, having been trained in radically different domains.  In the past people, notably including Risto, have rationalized the possibilty of such valuations in terms of supplies and the subsumption of pre-existing value into the value of bitcoin.  But what if we instead consider marginal flows, and admit the possibility that bitcoin may create novel economic value - value the magnitude of which we can not presently estimate and therefore can not rationally limit or circumscribe.

Bitcoin ETP would trade against perhaps as much as 1 mm btc of float.  The market cap of a single exchange traded company may range as high as 1 tn usd.  Btc represents not just a single company but an entire economy.  1 marginal dollar of moneyflow can easily move price enough to result in 10 additional dollars of market cap.   If ETPs on 1 mm float were to attract 1 tn in investor funds ( and there exist single investors each capable of investing about that much, such as Norway and PIMCO), which resulted in a market cap float of 10 tn,  then each bitcoin would be trading for 10 mm usd.

The scenario is perhaps unlikely, but it is entirely conceivable and I know of no credible or principled way to rule it out.  I could rationalize an additional factor of 10 if pressed -- after all, you can never have too much overkill.

If btc is replaced by another crypto, whatever value would have accrued in btc will just accrue in newcoin instead - even more , in as much as newcoin will only be able to displace btc by offering  an order of magnitude improvement in utility.