Thande decided to use Star Wars as a setting after the success of Luaky Commer because, like Harry Potter, most of the Board members were familiar with the films and the famous lines, so Thande could spoof them effectively.
He considered reversing the Empire/Republic roles (because, being British, the Empire are always the good guys) but elected not to in the end. However, he did get revenge on Lucas by making all the Imperial Thread Destroyer captains have 'evil American' accents.
Supposedly subtle references in the original are turned up to blatantly obvious ones, e.g. making the Trade Federation into the World Trade Organisation and the Corporate Alliance into the Evil Capitalist Combine of Wal-Mart and Microsoft.
With the prequel films, Thande struggled for a while because 1) people tend to be less familiar with the scripts and 2) the films themselves parody Star Wars so much that it's hard to add another layer. He eventually overcame that problem by inserting a continuous breaking of the fourth wall, with himself starring as the megalomaniacal Lucas-type director steadily descending into madness as he remains convinced that the new prequel films are so much better than the classic trilogy.