You now, in my experience we have a lot of employee and the best way is to train interested man, than just to hire a specialist, these project is not Pepsi selling company. However, here need to think critically , be responsible and be interested in future.
So, in my opinion, you should hire people with different knowledges in different projects, because you can be BEST promoter, but without mathematics your knowledge's only 30% of your potential. You need to find universal specialist. Moreover, don't scare to ask people - can they do this or that, how can you understand potential without interacting with person.