I’d try to install fresh spark plugs every 30-40k, this really seems to help reduce the tendency for ignition coils to go pop. If you did timing belt et.al around 100k I’d plan to do the next one around 170k-180k & also do a water pump & new coolant then as well. Since you’re 2004 you’ll pro...

Search for the DIY I posted a few yrs ago.
Basically add a few drops of oil on the shaft/bushing interface.

This has worked well for me.

PS: no bearing, just bushing in the blower motor.

I would just replace the blower yes, it's 15 years old, not the resistor. Oil the shaft if you don't mind going back in later this winter on the chance it fails then.

Good time to swap the cabin filer? Lysol the AC box?

My 2 cents...

- if you have ~ 200K miles, replace it. I forgot who made it, probably Behr. Do your research before buying it. Some ppl break the tab for the 5th screw. Some saved it.

- If you have ~ 100K miles, oil it.

You could have got a used reservoir with hose off ebay, this is the newer model that has no longer that brass piece inside https://www.ebay.com/itm/99-07-OEM-Volvo-S60-V70-S80-S70-Power-Steering-Fluid-Reservoir-w-Suction-Hose/114473850732?epid=1328922710&hash=item1aa72c576c%3Ag%3AXgwAAOSwLsFfjw8...