Wuzzard
First Post
I would fix your trap in a number of ways. Firstly, I would telegraph it by having a section of the floor already having collapsed - a previous visitor stepped in the wrong place. This adds immediate tension. Secondly, I'd place it in a location that requires the players to operate under time pressure -- an enemy is fleeing and they're pursuing and/or they're being chased, or some other plot reason. Or, alternatively, I'd have the trap area as part of an encounter with hostiles -- preferably ones that aren't vulnerable to the trap such as fliers or climbers or light enough to not cause the floor to fall. Either way, I'd make the determination of the rotten areas easier (but not automatic) because the trap at that point isn't a gotcha but an obstacle that enhances the area. Finally, I'd likely reduce the effects of a failure to an easy encounter at the bottom or a forced change of location (slide, new level, etc.) This enhances play because it causes the party to have to make the choice between risking a rescue or voluntarily entering the new area to stay together. It makes the dungeon/encounter area more dynamic. This is the only thing I liked about your trap design above -- it's failure mode did add a dynamic new area and a new traversal method.
You've turned the trap into a combat encounter environment facet. That's fabulous, and it makes the combat much more interesting. But its no longer a trap. Traps are exploration pillar fun, not combat fun. You can put traps into combat, but unless the players have the time to sweat it out, debate and try crazy stunts, its not a trap worth having.