Temperature of Power Driver ICs
Examine the widths of all traces connecting to your Driver IC.

If you can widen some of those, particularly those running over GND planes (or VDD planes), you can greatly LOWER the Driver temperature.

Copper traces have 70 &deg; C thermal resistance per watt PER SQUARE of foil.

A long thin trace, perhaps 1 inch by 0.05 inch wide, has 20 squares of foil and thus 20 * 70 = 1,400 &deg; C thermal gradient PER WATT.

On the other hand, if you can connect your Driver IC to the GROUND PLANE directly, with no trace needed, then Rthermal may be 70/2 or 70/3 = 22 &deg; C. Which should reduce your 90 &deg; C and boost reliability.

==============================

In this thermal design, I'm assuming the ground/power planes are much cooler than the Driver IC, thus increasing the heat flow from the IC to the PLANES -------- is a very good thing to consider.