I would simply implement the Mac Mini into your system as is for the time being. Get the basics functional and become familiar with its sound. I run my straight out. I'm not headless as it is connected to my HDTV but most times I am using my iPad with either the Apple Remote app (iTunes/Audivrana) or JRemote (JRiver for Mac) to control playback.
You have plenty of time to research and decide if you need to add anything else. Enjoy your music for now.
You have plenty of time to research and decide if you need to add anything else. Enjoy your music for now.