YAY! You're going back to Pi Phi! Woo hoo! You definitely have made me proud. I just got a rush update from another alum, and I know the chapter has great things planned for the week. You're going to love it. Heck yes, I'm biased!
But in fairness, I'll repeat that you should keep your options open. Look around at the actives in every chapter and ask yourself if you feel like you would fit in there. Do you feel comfortable there, or are you having to put up a front? You can fake it for a week, but not for four years. When you feel at home, you've found your place.