Personally, I use YYMMcNNNN, so a filename will look like 0805a1234. YYMM is obvious. the single 'c' alpha character used to be an underscore but I recently changed that to an alpha character camera ID since I now shoot with two different cameras that the NNNN part, the unique filename number that the camera creates, may overlap (one camera just rolled over 9,999 so is back in the 0100's at this point and I just purchased a second body (same camera make/model) that I'm approaching the 0100's as well). I can always sort by capture time if I want a chronological order to my images.
Since all my digital photography started after 2001, I can safely use the YY model rather than YYYY. If I scan any previous images to this, or have an image of unknown origin, I assign it a 00 for the year. Using 4 digits for the NNNN part allows me 9,999 shots before rolling over and like you, I seriously doubt I'd be shooting over 10K images on any one camera in a given month.
When shooting airshows I can do several thousand images PER DAY, although obviously the airshow only lasts for a few days. And when working on wildlife safaris I can easily average >500/day. So 9999 shots per month could be asking for occasional trouble.
Also note that (at least with the Canon cameras, I presume Nikon does similar things) if you end up moving cards between camera bodies then each camera will increment the counter to the greater of: it's internal counter and the last file on the card. So with camera A on 0123 and camera B on 9989, if you end up swapping cards (e.g. you take them out to ingest, but hurriedly reload them when an elephant charges your campsite) then both cameras will be shooting from 9990, and it won't take camera A long to wrap around and re-use the numbers from earlier in the day
. I find that having a rule where you only use particular cards in particular cameras isn't flexible enough for real-world use: it will fall over at some point.
Currently I'm still using YYYYMMDDhhmm_ID (where ID is a globally-unique counter). Because ID is globally unique I could omit the date/time from the filename, or I could shorten it to YYYYMMDD or even YYMM. But for a long time I've been used to having files in Finder/Explorer sorted in chronological order so I'm still using the full date/time info. I may change at some point, but old habits die hard...