How much query is acceptable for a wordpress multi site with buddypress?

Hi! I am just wondering how many queries is acceptable for a wordpress multi-site with buddypress?
I have this project that needs the following plugins with in a wordpress ms with buddypress.
- Pro Sites
- Membership
- Classified

Using this three plugins already gives me about 63 queries.
I will still be using gravity forms and some other plugin, plus the queries that will be needed for the loops in my template? and probably also use multi db and multi domain and domain mapping.

My project consist of 3 different types of user.
- Typical member to allow them to use an online planner using members plugin
- A member to create his/her own site using pro sites plugin
- A service provider to advertise their services using classifieds plugin

I think this is more of an optimization question. Using this plugin will definitely use to much queries. Do you have any suggestion what i can do to optimize this so that my application would run better?

Is it possible to do it this way? Like split the use of plugin for example

http://www.sitename.com <- For membership plugin
http://www.sitename.com/free-website-blog/ <- using membership plugin + pro-sites plugin
http://www.sitename.com/classifieds/ <- using membership plugin + classifieds

So this will be 3 installation of wordpress ms with different plugins activated? but the thing is if I network activate a plugin it will be automatically activated to the whole network right?

Hope you guys can point me in the right direction. Thanks!