https://forum.atlas-games.com/t/card-board-games-archive-links/116/1
We discussed increasing size to increase strength, with a corresponding decrease in quickness. Whether or not this applies to Hrermetic magic...?
But as far as a bonus to strength in Muto Corpus, my feeling is that this is the realm of Creo Corpus, only as a specific effect, whereas the Muto Corpus effect is indirect increases in strength and decreases in Quickness as a consequence of increasing size.