If the bitcoin does not increase block size or the transaction is congested, the price of altcoin will rise a lot.
I agree with that. It is the reason why many altcoins are rising fast.
My be it is a valid reason,because when ever new people enter the alt coin market,they see the price of bitcoin really high and i do think they will hesitate to invest in it and they would scout for alternatives and so is the reason we are seeing huge rallies in all the coins,when it comes to Zcash to reach 0.2 btc means an increase of 100% from the current valuation ,which i think is impossible at this stage .
Possible the price to increase 0.2 because zcash have potential to increase they have big future. But in this year maybe befpre the end of this year 2017 the price will be 0.15 and the price in 2018 maybe 0.2 but no one knows what is the exact amount of zcash in the future. It depends on the demand of the market.