...in the long term it should be 25 % of BTC.
If there were no such phenomena as network effects & 1st mover advantages, sure. It'd be worth 1/4 of bitcoin, in a constantly diluting pool of crypto-currencies, as each new one comes online to claim a slice of the pie.
But that's not how it works. Bitcoin should continue to enjoy a valuation at least an order of magnitude more than that 1/4 analysis suggests, due to the network effects it enjoys; ie, it benefits both the existing users as well as each new entrant, for each new entrant to primarily use bitcoin as opposed to an alt with far far less usage (unless there are huge feature/technical advantages to a given alt). That's not say litecoin will have zero value, but please realize that the real-world relative valuation doesn't come purely from the 4:1 supply ratio.
