PM suggestions?

You don't need to do the trans or coolants or pcv valve or spark plugs. Wait for the 120,000 service.
The EGR system, you probably don't need to do that just yet. It certainly wouldn't hurt to do it.

No reason to do the water pump, it's probably good for another 100,000 miles.
Wouldn't hurt to clean the fan. Did the other owners have dogs in the back seat?
Since it has that pull out filter, that will stop most of the fur, but not the dirt. You can get
a sheet of a/c washable filter and cut a piece to fit. That's what I did.

Check the brakes. Might be a good idea to clean the slide pins on the front and rear calipers.

 

It would make a lot of sense to do the spark plugs, because it’s very labor intensive to access the plugs. However, you’re doing that labor as part of the EGR clean. What you can also do with everything apart is clean the firewall area thoroughly, especially the cabin air intake area, as best as you can. Keeps the cabin air fresher smelling.

 

?????What???
Spark plugs are easy. It's a 15-20 minute job to replace the wiper cowl and assembly.
A minute or two to remove the coils. A minute or two to remove and install the plugs.
Just make sure you have 14mm magnetic spark plut socket.

 

If you're going to do all the work yourself, I would go ahead and take care of everything. You're already at the 8 year mark and most of this stuff is done at the 10 year mark. It'll cost about $100 more in parts, but that's nothing for another 60k - 100k. I would save the water pump replacement until your next coolant replacement (another 50k) miles.

So I would go ahead and change the plugs and coolant while you're in there. If your 12v battery is over 6 years old, I would consider changing that out as well.

 

Sometimes when you change out a perfectly good part, you can replace it with an inferior part and cause problems. Problems you never had before, just because you decide to change something that wasn't an issue. I've seen this way too many times

 

I don't know anything about infant mortality, but I do hang around an autoshop a few times a week. One of the stranger things recently are water pumps failing from 2.5L Toyota engines. Similar water pumps in the 1.8L Prius. Those water pumps are just seizing up for no reason and many are just a few years old. Maybe there was a bad batch back then but that is the reason I don't like changing out good parts (in your case from 2015). These are made to go more than 150k miles. If you change out a perfectly good part, you can put a brand new one in from a bad batch and end up with problems (not even taking into account of human error with installation)