Leaves in first layer of Hugel?

I have gathered my supplies, and was thinking I would start my first layer as leaves, instead of paper and cardboard.  Then follow up with the bigger wood.... etc..

I am not digging out, to drop my Hugel beds.  Max, i have  10 inches of "topsoil" that is probably half clay (very slippery stuff) with gray clay below that.  Long story short I am not going to dig in the muck and make a puddle, just to fill it unless someone tells me i am making a mistake.

so i guess thats 2 questions. 

hope you can help

I did mine on top of the soil rather than digging a trench..and they worked out really nice..