This comes down to a lot of things. The level of the players playing, the map, and can also be affected by flag settings, as well as revival times. Its hard to tell what you'd change it to with all of these relating to it somehow.
Something I thought of though is letting the map designer choose his/her own timelimit, fraglimit, elim and such, so the map can be played as the designer has wanted it to be played. This would obviously be incompatible with old maps, but I see it as a way of enhancing the gameplay of a particular map. Obviously this could be flawed with people being idiotic with the limits, but restrictions could be set, plus it wouldn't make it through beta stages if it was completely messed up.