Lithium protection circuit design
Most battery protection circuits use a chip (eg. Seiko) with a pair of  external MOSFETs for charge and discharge voltage protection. Also overcurrent protection with PTCs.  

Specific product recommendations are off-topic, but you can look at Seiko's line-up and compare. 

Advantages are that most of the design work has been done for you, the parts are guaranteed with reasonable voltage tolerances, appropriately low operating current (uA) and they are inexpensive in large volume. Parts count and size is also reasonable enough that they can be included in the cell housing.