Bitcoin and a lot of altcoins should be about 10x what they in reality are... This would put altcoins at same level as two years ago before the big climb. One can't just speculate price of Bitcoin based on its own price as number of altcoins is constantly increasing and that means Bitcoin must adapt or people will trade against other coins, including LTC and ETH.
It's just really difficult to say what something "should" be worth when it has no earnings, cash flows, or dividends. People have different definitions of what gives each project value. Some use user numbers, number of apps, transactions, cost of production etc etc etc. It's just tough to say what something is actually worth in this space. It's technically worth whatever the market says its worth. :)
It's easy with coins that have premine (with or without ICO), as the premine must cover all operating costs for whole lifespan of the coin. As such premine divided by total operating costs equal to value of one coin.
For coins without premine or ICO, the amount of mined coins per month need to cover the mining related expenses, so value for one user can be quite different than value for another user. For members of development team, value of mined coins need to also cover expenses related to operating the coin infrastructure.
Well that would give you the initial selling price of the coin, but the market price could and likely will be very different...
Think about my coin... first sells were at 8 sats, but pressure is for it to go up to 950-1000 sats... That's quite big difference.