So assuming that a really good alt-coin could reach 10% market while bitcoin should have between 30% to 50% at most times, then if we take for example digibyte(DGB) that has 21.000.000 max coins, its 1000 times the amount of bitcoin
so even if DGB is a huge success and holds 10% of market, and bitcoin holds 50% .. dgb value should be 1/5000 of the value of bitcoin
putting a moreorless low value for btc like 15000 that would allow dgb to go up until 3 USD

but outside of this example, do you think this is a valid way to calculate the possible maximum value of a coin?