The unbeatable package would be engines around 600 hp and #6 drives. Drives aren't a maintenance issue, the #6 on the race boat that were powered with hp500s were complete maintenance free, except change the oil at the end of the season.
Engines are another big question, I think the way to go is with larger displacement making less hp. My 509s don't make a lot of HP but they are gas and go except for changing the oil every 20 - 25 hours. I'd love to have 572s making around 600 to 650. With the short season here in NJ I want to use my boat and I'm willing to give up a few mph to do so.