Power factor requirement for SMPS just above 75W
What about PF in between 75W - 160W? Does it have to comply with any
requirements?

From this wiki page and take particular note of the final sentence: -

In 2001, the European Union put into effect the standard
IEC/EN61000-3-2 to set limits on the harmonics of the AC input current
up to the 40th harmonic for equipment above 75 W. The standard defines
four classes of equipment depending on its type and current waveform.
The most rigorous limits (class D) are established for personal
computers, computer monitors, and TV receivers. To comply with these
requirements, modern switched-mode power supplies normally include an
additional power factor correction (PFC) stage.

If you dig around you can find tables like this: -

Source document that has the above table and other good information on this subject.
Here's another good bit of reading material. And, another useful link.