One wish take easy advantage of the packages/codes buildt through our engagement with mathematica.
Through building packages I see that I have made several functions which are simple and closely related. However, I would prefer one function with several options instead of many simple.
I therefore wish to make a collection of ideas and examples, could be your own code, code located on this page or any other that show good practice of adding options to functions. Efficient smart/neat solutions that can be extended to arbitrarily large functions is appreciated.
It is also easier to remember how to use the custom functions if they reassemble built in functions.I wish to provide an example Stefans answere of how an expansion where you can query certain properties using a string, very similar to LinearModelFit, even though I would assume that the code behind is very very different.
Hopefully answer to this question would help the reader get an idea of how one can expand and add functionality to one function in a good way. I sure know that good examples definitely would help me.
I would like to point out that any change/edit of the question that would increase its usefulness is appreciated!