I understand the intent behind this, but doubling the timer would make your wait BEFORE you get into the dungeon MUCH longer. Removing it would potentially lead to needing several hours free to have a chance of getting in one dungeon run. Depending on what you're running, there'd be a chance you'd spend your whole free time on the game waiting and never get in.
If you don't want to wait for your DF random pug odds to improve, you could use the Party Finder and/or shout for a static group to attempt the content with from within your own server.