It probably would put you over the top for now. I've heard folks with more "established" tanks can go over the 1 inch per US gallon rule, but I'm not going to recommend it. I'm still a newbie myself, but like you, I fell in love with tiger barbs. Someone else mentioned the five banded barbs to me, and thought I would pass that information along. It may not help you for some time, or at all. Perhaps someone else interested in tigers will happen through the thread, and it will help them.
I'm not suggesting that you get five banded barbs, but I am offering that they are a less aggressive alternative. (Also, I believe they are less bulky than tigers. Tigers grow up to 3 inches, and I believe the five banded only get to 2 inches on average, although some do grow bigger from what I've read.)