First, I agree with Scott - rent bikes and ride it a few times.

As you noted, I think the biggest reason for shorter cranks and higher BBs is saftety - to reduce the chances of a pedal strike, which are likely to cause your rear tire to lift and then you slide off the track. (Some will argue it's about RPMs.)

That said, I ride 170s. I have long legs, and my fitter thinks it fits me better. My bike also has a fairly low BB for track bikes though I think it complies with the track mimiums. My home track is also 42 degree banking.

I have clipped a pedal solidly and slipped once. I have rubbed my pedal many, many times. In fact, my straps have clear wear on them from scraping the concrete track. It does take some finesse and awareness to run 170s on my home track.

If you are new, it is probably a better idea to run shorter cranks. If you read through this forum enough, you'll find that most people change track frames pretty frequently in their first few years of riding and racing, as you learn more about what you want and dial things in.