Interesting. My reasoning behind the one tile thing was that I didn't expect people would actually try to make things compatible - I expected a black tile, a letter block, a random ground thing, maybe a spike, just lots of random stuff like some tilesets are actually composed of. You are perhaps right that it would have made more sense to let people add more than one tile, maybe without the weekly thing.
...I'd try that next month, but I'm not going to be home for much of it... if anyone else wants to try a freer version of this, go ahead.