Do what we all did before the fancy shmancy internet and all these calculators. Grow a pair, make a decision, put some gears in. If you don't like it, change it again. Gears are what......150 bucks?
LOL, that's the primitive caveman approach. Nothing wrong with asking advice from people who have already been there, and the RPM calculators are great, I use the one on Randy's ring and pinion page and it's always accurate.
When I raced for 21 years I would just throw 4.56 gears and an 8" converter in the car and go racing. Now that I have a street car I play around with gearing and hope to try a tighter converter soon, it's way cheaper than paying for an overdrive setup.