Sorry I'm late :-)
Well, 200.000km was last main tune up - belts, spark plugs, water pump all that was recommended by lexus dealer. PCV valve, that one I don't know. How would it behave, when something was wrong with PCV valve? I do change oil every 7.000km with oil filter, air filter every 14.000km, fuel filter every 21.000km - car is mostly driven in city. Equivalent for Dexron III is Donax TX.
Year ago I had a strange problem, engine check showed up and RPM was high on idle, even when the engine was warmed up. Diagnostics said that it is AIC, so I googled what to do about this problem and it just needed to clean it gently. It is fine, but there is another strange problem, I think it could be clutch. When driving at higher speeds (above 70km/h), the engine is not holding the RPM, so I don't brake with engine anymore, But I think it did few years ago. And I have another problem, that spark plugs that I bought for another change are NGK BKR5EP-11 for GS300 and for ES300 are BKR6EP-11.
My head is starting to ache