No such thing as an average temp really exists because average temps are heavily dependent on ambient temperatures.
That said, the MSI Gaming X also doesn't turn on the fans until the GPU hits 60C and above, so it's default is to hover around 60C at use.
Better case airflow can help, but only if your room/where the PC is actually cool enough for that to matter. If the area the PC is sitting in has dead air, the hot air being vented from the case may have nowhere to go and will just cycle back through the intakes.