this is a sure fail safe method even for cooking small amounts. the smallest amount of rice i have cooked is half a cup in a pot. everything is play be ear, or rather by sight.
whatever method you like best, at the end of the day i still think the basic rice cooker is still the most efficient. my trusty national rice cooker comes with just keep warm function, from the 80's. then it was the best rice cooker around and to me still is. to avoid caking, unplug the cooker once the switch has flipped & let it stand for about 45 min. guaranteed nothing sticks to the bottom.
my ideal rice cooker would be a fully automatic one. all i need to do is dump the rice into cooker & flip the switch. the cooker will then sense the type of rice & quantity. of course it would have a voice confirmation before activating the best wash cycle & cooking mode ...