Multisite group themes question

Hi,

I am building a multisite using prosites from wpmudev, I want to help some friends building websites, selling monthly accounts and stuff.

I’m at the step at choosing witch theme framework to work with. There is many business out there that sells a lot of themes and I have some questions about what I should aim for.

First, I think that to limit conflicts and errors, I should choose one or two framework maximum. For exemple, I have Dante theme and Dynamix theme, both of witch comes with a set of plugins and a different page builder. If I have too many of those great themes on the same multisite, I’m afraid it will complicate my life, in therm of plugin management and in therm of possible bugs…. Am I wrong?

Second, I think I want to work with bootstrap 3.0 based themes. I like those, the fa-icons and other features seems a great choice for me. But I don’t see many business that makes sets of themes based on bootstrap. The themes I’ve found so far are sold on themeforest or other web markets. With themeforest I have to buy a quite expensive developer account to make multiple use of the themes. Other markets have cheaper multi-use account, but I’m not so sure about the quality of a 15$ theme. And I think I will have to use a set of plugins with every new theme I buy, witch is not really what I seek for.

Third, I think my solution is to have 3 set of themes. One for basic accounts with basic themes. A framework like the genesis framework for medium account and a set of themes available for super users with 4 or 5 thèmes based on bootstrap. Is it too complicated. Should I just use as many bootstrap themes that I like with their specifications, plugins and interactions, without fear of making the whole site slow and buggy?

Or maybe somebody can indicate me a business that makes all their themes based on bootstrap with some plugins that work for any of their themes?

I really wonder what the community think about this subject….

Many thanks

Francois