Bob was never one to do the bare minimum, whether it was with a performance or a scheme. Were it possible for Bob to cause an earthquake, that earthquake would be a nine on the Richter scale, or at least an eight. He needed to make a major impact before he was satisfied with anything. Great men didn't end up in the history books by doing just a little, and life wasn't worth living without the odd risk. Nor was life worthwhile if you couldn't enjoy whatever you did.
Explosions had to be big. He'd been so disappointed at the tiny wisp of smoke from the old atom bomb.
In his vengeful fantasies, he never just killed Bart. He was quite slow and sadistic about it, cackling like a villain in a Disney movie. Everyone knew villains were always the most interesting characters, because they put their all into what they did. Or at least, their actors did.
Bob had little respect for apathetic people, like Krusty or Selma. They would rather just be dull and miserable. Everything about Selma was utterly bland: her appearance, her home, her dead-end job and her droning voice. And those awful slideshows she and Patty made caused even the most interesting places to seem boring.
Actually, perhaps blandness was a trait hereditary in the Bouvier family. During the time Bob stayed with the Simpsons, he thought Marge's cooking had little creativity. Her chicken had no seasoning, and her pasta had butter, but no sauce. She had declined Bob's offers to improve her recipes.
When Bob read to the children on TV, he did so in the loudest voice possible. It worked, as they did seem to become sincerely invested in The Man in the Iron Mask.
When Bob performed, there had to be costumes and sets. He'd gone through an awful lot of trouble to make costumes and a little set when performing HMS Pinafore for Bart. In hindsight, this had helped Bart stay alive, but at the time, Bob had simply wanted to make the show more interesting. After all, Bob had meant for it to be the last thing Bart ever saw, so why not let him be as entertained as possible?
Speaking of Gilbert and Sullivan, Bob shouldn't have enjoyed tormenting Milhouse with operetta to the extent that he did. He could have sung just enough to crack Milhouse, but the boy's misery was so amusing that Bob kept going. He liked a captive audience, both in the figurative and literal sense.
Bob might have shared common ground with Bart Simpson in his desire for attention and willingness to be audacious, but if Bob recognized such a similarity between himself and his arch-nemesis, he would never admit it.