welcome. 2nd the vote for randy and todd to help out they just did the stage III work on my allroad and I am loving it.
as for extra punch, a chip will do wonders to a 1.8T, but yes, your warranty will be at risk. I waited until the warranty was up before doing my chip.
other than a chip, consider exhaust, or some handling mods - new wheels and tires will do wonders, as will sway bars and different spring.