Iceman is another prime example of this growth. At first he was just a snow covered clown, then an icy shell. Then he got zapped by Loki to god-like cold generation. He finally got control of that and was able to function without his inhibitor belt. Then he finally figures out how to increase his mass (giant iced spikes and super dense armor, giant icy fists, larger than man-sized buffed by super dense icecular muscles). And then lastly, he can now turn his body into ice itself giving him virtual indestructability (he simply reforms himself) and the ability to alter his form.
I'd love to see write ups for each of his various 'phases' of his growth.
He probably started at 250pts, then after some exp added armor and a transform ability to create ice-based constructs and objects. Then a permanent powerful cold damage area effect always on. After a while he pays off the points of the always on disadvantage (which was also helped by an OAF focus, the inhibitor belt). Eventually he then added growth and other body-based powers (tougher armor, damage shield for the spiked armor, +HA area effect of super huge icy fists, increased strength linked to ice armor, Growth as he adds more ice to his mass, etc). After this he gets creative with his ability and adds the 'gimmick' effects. Enhanced sense to detect the changes in temperatures, ability to freeze water molecules in targets to cause unconsciousness or death, etc. Finally I'd say as he is now, around 500pts with a multiform or shapechange ability to count for his pure ice form.