Space Center Visit

Hi! I had three questions about visiting space center houston for the first time:

1. For non-membership tickets, they have $30 vs $45, with the difference being the Historical Mission Control tram tour included in the more expensive ticket — any recommendations if general admission for $30 is fine or if the $45 is worth it?
2. For the membership that is $65, it says you can bring an additional guest for a discounted price, but it doesn't mention what that price is — does anyone know?
3. Does membership also include the mission control tours, and if not, how much do you pay for that on its own?