Which bit is harsher?

Regardless of which bit is more harsh, the best one to go with is the bit she seems to respond better to and seems happier in. Any type of bit can be harsh if your are constantly in their face having to fix them. A smooth mouth snaffle can be more harsh than a high port if you constantly have to pick at them. If she does well in the first bit and you can stay out of her face then that is probably the way to go. The fact is that it is legal even if it's just barely legal.