If you have an oversize tub, but don’t have a tankless water heater, you should fill the tub with hot water only. The “hot” water will be cold before the level gets to where it needs to be, and you can continue the flow to adjust the temperature as needed. If you start it out at the correct temperature, and don’t pay very close attention, it will be unpleasantly cold by the time it gets full.
I took my first bath in probably a decade a few hours ago. Primarily because it was the most comfortable way I could think of to clean the splashed soap, oatmeal, and God only knows what else from the area on the far side of the tub. I figured out my hot water mistake in time to have a warm (but not hot) bath.