What are the sub-user limits in different plans?

It looks like I can only have one extra user on my plan ? I would like to add one other view only person.. 

what are my options if i want to upgrade ? 

You have been grandfathered to the sub-user plan. So you would be getting the following limits if you upgrade to our plan.

Starter: 1 sub-user.

Bronze: 3 sub-user.

Silver: 10 sub-user.

Gold: 100 sub-user.

Let us know if you need further assistance.

Thanks.