Thanks for all your input, Amanda. I am now giving some serious thought to how a backdrop type feature might be incorporated to add to the dynamics... perhaps emulating a large cave somehow.
To answer; the tank is a breeze to clean now. There is one piece of drift that has a shape which traps all of the waste under it. I clean that stuff up almost every day by sliding the drift over with the spihon tube then sucking up all the stuff it reveals. I get almost 100% of the junk in about ten seconds.