Increasing the descent time will not change a warrior party with 2-3 priest. The problems is once you introduce party cure on a lvl 72 cap server warriors become more tanky. Without CC, every class will die fast. Secondly, a warrior party with 2-3 priest is the ONLY way to combat mage parties. And, even with 2-3 priest it can be a challenge to defeat a full mage party.
My suggestion would be to DECREASE the range of CC. The range of CC on this server is very large.