Please see my comment to the question. Your question might be based on some your misconception or maybe the conception you do not explain.
The relationships should not really be quantified by the total number of them or something like that. And "a lot of relations" does not have to mean "a lot of queries", it you do it right. The structure of relations should be defined by the structure of actual knowledge
you want to represent with a database. Perhaps you need to start approaching it all by learning about such thing as database normalization
You should also understand, that one of the most important principles here is the "Don't Repeat Yourself" principle:
And then you will be able to look for the optimization: