Best practice for doc design

I am wondering what the performance impact will be if I store for example notes in my main doc vs in a reference doc. Let’s say I know the size of notes in my doc will be minimal maybe 10 or so. Should I store each note in a separate document and only store link in my main doc. The benefit of stirring in a separate doc would be that I can just create a new doc and if I update the doc I don’t have to do a subdoc update. Still trying to figure out what the best aproach would be as this will help me create a good design to build on.