I like this post, for me I'd have to say something extremely large. There is a 7500 gallon tank here in Houston at one of our LFS's. It is awesome, even has 8 ft. trees in there along with tons of rocks, live grass, huge driftwood etc. This tank has tons of fish from everywhere including africans and along the floor there are tiny fry everywhere.
So, I'd like to have that same tank and as far as what to put in it. My African Dream would be to go to Malawi myself and scuba dive down in there and personally net as many as I could and fill my own tank myself.
That would be awesome...