Nothing wrong with those oil temps. You dont want low oil temps as the engine and oil are made to work at those temps. Usually from 80-100C is a good operating temp.

Charge air temp and engine oil temp are two very different things in relation to their effect and where they operate.

With everything temp wise what you want is stability. 90C coolant temps are perfectly acceptable but if it sky rockets at the slightest addition of load then you have an issue. And for the most part it wont be the radiator at fault but poor system maintenance or poor airflow. A radiator will nearly always work at around 10 degress temp drop across the core with adequate air supply no matter its size. (In perspective of course)