Its just an added bonus for you. There were more than 1 version of some of the cards painted and experimented with. It could have been to add a bonus to the pack and use up the whole printing sheet before the cards were cut.
Or we could come up with some fantastic magical reason
Some people select one of the Magus cards to use and take the other two out of the deck.
Its not strange for s tarot deck to feel like that, many people feel the same way.
'Mirror of the soul' is a good name. For me, the 'soul' is that distinctly human function of the imagination that creates multiple reality patterns, extensions and possible scenarios and their solutions that can be mentally visualized and enacted. In some cases it operates through a set of 'themes' that can be reversed, interchanged and rearranged in context with each other.
So we end up with stories, epics, adventures and even life patterns that can have reflection in 'mythological' patterns. Tarot seems to be a type of handbook or 'flash cards' for such 'soul processes' .
hence, it can have a deep resonance with one. In a way, it is the pentacle ( ie. the whole deck is the pentacle ) of the magician.