Stories with shrinking never seen to take into account the Square-Cube law. I'm trying to consider what it would take to do a story like this that actually fully addresses the square cube law. I know most of the advantages humans would gain, such as:
1) being proportionally stronger, able to lift far more then 50 times their weight and survive drops from, quite possibly, any height thanks to terminal velocity
2) being much stronger then any insects or bugs of the same size they run into, thanks to having a body designed to have far more muscle and strength then creatures adapted to take advantage of the square-cube law.
However, I'm wondering what disadvantages they would face. For instance, I assume they would be quite cold, perhaps even dangerously so, since they can't rely on producing enough internal body heat? What similar down sides, even lethal ones, would someone face being scaled down to that size? For that matter what other advantages or otherwise odd effects would they experience?
To be clear I'm only interested in effects caused by the square-cube law. I can anticipate all the standard threats that come from being afraid of being stepped on etc (then again, would we be in danger of being stepped on? we may be able to survive that...)