This is not a fault of the nano design but rather a lack of understanding of functional differences.
Nano is simply a tank that holds liquid. No different than a standard or XL carto tank.
The difference is in what goes on in the coil chamber(like Cartos) Length makes a difference. Difference means possible change is needed.
With a Nano< Short> tank kit, you receive a Short Chimney cap. Your lips and consequently, your throat/lungs are Closer to the Coil. If you were already enjoying a nice warm Vape, it may become a Harsh Hot vape. Sometimes interpreted as burnt.
This simply means you need to reduce power a bit, if using a regulated mod or Re-coil at a bit higher resistance if on a Mechanical.
Do not accept as gospel, the recommended resistances others claim are right. It is what works for you that is key.
I run my Kayfuns from 1.3-1.8ohms. Some go as low as .7ohms and others up to 2.8ohms.
This is something each individual has to work out.
You don't throw the baby out because the bath water is to hot. You make the necessary adjustments.
Nano's - I have 6 kayfuns, 4 in nano and 2 different styles. My Nano KF's vape exactly like the standards.
The typical Nano kit actually only holds 1.7-2 Ml. I can empty one in under 2 hours.( First is size and second is good wicking.)
Mt Top Cap Nano's Are no larger and last several hours. They are all god for reduced use for special or rich flavors that are no ADV's.
My ADV favorites go in the Full size and travel with me.