Forget the HOS Express passes. I'd recommend doing the Fright Feast dinner. You get food and you get to see the HOS show in the Timbuktu area. Best of all, you can hit the houses 30-45 minutes before the general public. This way, you can have the houses all to yourself. I did the Fright Feast last year and got into the houses early. I walked through the Hunted all by myself and nearly every Scare-actor got me! That was a pretty intense experience.
The Fright Feast also forces you to get to the park early. I usually try to arrive in the parking lot at 5:30, 6 pm at the latest. During the first year of HOS, I hung around my hotel less than 1 mile away from Busch Gardens. I waited until 6:30 to depart, thinking I'd have enough time to travel and buy tickets. I was stuck in traffic all around BGA until around 8. Then I had to wait an hour for tickets and I was in the park by 9. By that time, all the houses had over a 90 minute wait! I did the same thing on a 2nd visit to HOS during the 2nd year and I was stuck in traffic too.
So for HOS, I always try to arrive over 90 minutes early and buy my tickets on time. I remember one year I was at the top of Montu's lift hill at 7 pm and saw traffic backed up on all roads to BGA!