Group Sales Online Pricing Rules

Has anyone found success implementing group pricing online? We are hoping to make it possible for our smaller groups (10-14) to purchase tickets online with the same discount we offer via email/phone. We intend to use seat volume rules with a price type change to maintain consistency with our other group orders. However, I'm struggling to find a way to maintain the best discount for all patrons. We offer multiple price types online, which we'd like to include as part of the total ticket count. Our Under 35 rate is steeper than the group discount we are offering, so we'd like to leave that price type as is, while discounting the others. Is there any way to select which price types are included in the price type change? If not, what are other possible considerations?

Thanks for your thoughts!

Arielle