The value of cryptocoins is derived from the level of encryption (that is, difficulty). It has nothing to do with the supply limit which is probably a technical issue. In the future, coins with limited supply will have a big problem - no one will have an interest in mining them because there will be no reward.
Isn't what makes bit/altcoins so valuable is that there is a finite supply of them? Having an Infinite coin supply means that that miners will be the one who suffer if the coin ever had to be pick up in trend.. In the future, the only people that would be able to mine it would be those that have a large amount of mining resources or mine with a large pool.