It's an interesting dungeon - not least because there's no walls (apart from the outer wall) - but also because the positioning of the end zones encourages fairly immediate conflict between the two teams as they race for the chests. I didn't find that 1-square wide ledge was an issue (though I do like using chests as obstacles too, so maybe this is more a personal taste thing

). The use of water traps instead of walls does make things interesting with lots of precarious position rolls - but at the same time I can see that wardancers and the passing game could dominate here (the halfling throwing game could go either way...).
The way we view this dungeon, and others like it which predominately use pit traps rather than walls, will change once general obstacle leaping is added into the game. Depending on what rules Cyanide use for this it could either make these dungeons more exciting - or essentially turn them into simple flat plains with the occasional tripping hazard.