Ask HN: Startup Pricing Models when competing with Giants

We are building a startup that solves an existing problem but with an innovating approach and some extra features / benefits that existing competitors do not have. My question is about pricing.

If the competitors have say $18/month subscription charge, would it be better for me to give similar features at $ 9/month or $18/month or $ 25/month?

Also similarly for the Free plan, would it be better to twice as much free stuff or equal?

Any ideas, experience from existing founders along this line would be highly appreciated. Thanks in advance.