Maintenance Suggestions for 96 Suburban 2500

Hello Group,

I just bought a 96 Suburban 2500 4x4 with 7.4L with 138K miles and was making a list of preventive maintenance and wanted some input from the experienced ones. It will be a part time tow vehicle for my 31' travel trailer. The a/c blows warm so I am hoping it just needs freon but I have noticed that the electric fan in front doesn't come on when I turn on the a/c and neither the a/c compressor. It has a slight leak under the front differential so besides getting that fixed I wanted to get the front and rear diff fluid changed.

Oil change
Trans flush
Brake fluid flush
Engine coolant flush
Possible power steering fluid flush (if recommended here) since it also provides pressure for my brake system
spark plugs, cap/rotor possibly wires and PCV valve
Sea foam in tank possible some in oil pan and in PCV valve hose (not sure)
Cleaning of the TB and IAC with carb cleaner
Mass Air cleaned with the spray on and dry mass air cleaner (not carb cleaner)