There appears to be a lot of lashing of teeth on this subject, it's no big deal.
The basic rule is have a pair of droppers for each length of track. If you can get away with less, and it works, fine. No DCC inspectors coming along to inspect your work. Your the customer, and your the one who need to be satisfied, so if you want less track feeds fine.
Do put a track feed at each section of track, IE before and after a turnout. Yes you can have a ring main if you want. If you have set track and you dont want to put in 100's of droppers fine, try it with a few droppers, after all you can always add a few more if running in an area becomes erractic.
This is hobby it supposed to be fun, so enjoy your Hobby and DCC it will be fun