Replaced front brakes at 120K. What other services should I perform?

In my experience, uphill drives normally have little to no effect on battery temperature, but downhill "drives in the heat" will certainly make it shoot up, if significant regenerative braking is involved

 

The Gen 3 Prius is such a noisy beast at highway speeds that the fan may have been running just as noisily as before but it was drowned out by tire, engine, and wind noise.

I'd take a look at it if it was noisier after someone (even myself) had cleaned it. They may have not gotten the ducting installed right and so the battery isn't getting enough air. I've probably cleaned a hundred of them and they never make more noise afterward.

 

A lot of that is experience and perhaps a lift. The water pump is "if its not broke don't fix it". Aftermarket and counterfeits are often worse than leaving the original in. Reliability goes down the tube quickly without a real (not Amazon) Toyota water pump when the time comes. There are two. However if you get one of the overheat lights, stop immediately and have it towed. This is an aluminum block and head. When warped they are toast.

The two coolant systems should have had their antifreeze changed twice by now. This is more important by far than transaxle fluid.

The brake fluid should have a Techstream complete flush immediately. Some suspect the $2,500 brake booster failures could be reduced by this safety related brake fluid change that should be done anyway. A full flush ensures the master cylinder passages are all cleaned out.

You are getting into the range of major repairs on a gen3. Head gaskets are the worst and can take out the whole engine. The number one mitigation is oil changes and not every 10,000. You want fresh oil every 5,000 or six months. Like your wallet depends on it. It could save you $3,500-$5,000 in sudden engine repairs.

If you shop around, some dealers will give you a buy one get one free oil change. Other places are ok as long as its full synthetic and a good price. Some of the oil change places charge the same as a dealer.

Inverters can strand you as well. There is an extended warranty on them. Don't make a mistake and have someone else put in a used one. Toyota won't cover it unless its original.

Of course there is hv battery replacement likely around 150-200k miles. Be smart and start a repair fund now. When the time comes buy new cells or an assembly with new cells. Everything else will be a recurring disappointment.