Power pack, or the pro cal, is ford racing mild canned tune. You might feel a difference but that's usually to better throttle response. It will add some rwhp and rwtq but nothing like a tune from a reputable tuner or dyno tune.
If you stay n/a you can go with a 3400-3800 toque converter. Converter alone has made cars 60' from a 1.8 to a 1.5 easy. I'm going with a 3400 and should work with the nitrous too. It's the best bang for buck on these cars.
And I've seen a lucky few that have hit high 11's with tires alone.