Honestly, I use iceberg because its still quite crunchy. I think its similar to chinese leaf (to me anyway) I get bored having cold lettuce, cold salad, and thought why bother? Works well.
Stirfried cucumber is AMAZING. You have to peel it, and strip out the seeds in the middle. Best way to do this is peel it, cut in half lengthways and run a spoon down the middle to deseed. Cut into 1cm slices, and then stir fry with ginger, garlic, salt and a bit of powdered sweetner. Throw in a tablespoon of water to moisten it up a bit. beautiful. From the "Beyond baked beans green" cookbook. She serves it with rice but I suppose you could use cauli.