How much nicotine? It depends.
Like many of the others I started at 18mg. Over a period of a few months I reduced the PG content to where the juice vaped smooth then sometimes the nicotine level seemed to high for "chain vaping" and I started mixing 0mg VG in with my juice to reduce the nicotine levels.
I started switching between two tanks/mods while at home, one with 1/2 the nicotine level as the other one. I'd "chain vape" the lower one while getting a "extra kick" out of the other one from time to time.
Getting outfitted with "subohm" and "high flow" tanks did not change much. While I can still tolerate a higher nicotine level in my Aspire Nautilus tanks in the Subtank-Mini, Lemo2 and Atlantis2 I generally use slightly lower mg levels. I'm currently running 14mg and 3mg in my Nautilus tanks and with the sub ohm tanks 6-9mg. (I don't bother with the low mg nicotine level tanks as I have the Aspire tanks to cover that)
The 1st and foremost thing I noticed when going high volume (sub-ohm, high air flow, high power) was the raspy throat hit. Even the 14 and 12mg juice I had prepared for it was to hard to inhale. 2nd was the 'dizzy buzz' I got with having to high of a nicotine level. I mixed up some 6mg for the sub-tanks but that did not feel like enough so I mostly run unflavored 9mg 90-100% VG in my "main" tank and have a few mixes of 6mg flavored juice I rotate in them.
The best trick I picked up was getting a stock (+8oz) of 0mg 100% VG juice (and if you can stand it) a stock of 50/50 0mg juice to blend down the juices I already had. I still have over 8oz of 50/50 18mg unflavored to work my way through. (sigh)
So when is to little mg to little? IMHO when you find yourself chain vaping or craving a smoke you went to far and need to up your nicotine level.
