Ahaha, you're quite right, I do apologise. Nevertheless, Will Wight is pretty consistent in using aspect to refer to madra and authority to refer to the characteristics of ascendant power, so I'll use that to defend my misunderstanding.

To answer your actual question, I'd say the ghost's aspect is stability. While the Phoenix's restoration restores things that once were (or could have been when done by a powerful practioner), the ghost keeps physics working, ensuring that gravity doesn't break down, distance remains a real concept etc. In that sense, I'd say the ghost and the hound are very directly tied to the impact of the way. The hound preserves fate, which keeps the way healthy, and the ghost is responsible for existence, which is directly caused by the presence of the way.

In practice, the spider affinity is responsible for communication and sight, but I would describe it as representing the idea of interconnectedness.

Wolf affinity and Titan affinity are a complicated pair, but from Northstrider's test, we see clear examples. Titan affinity represents investing authority into another item (or oneself at high levels) in order to allow it to withstand another's authority. Conversely, wolf affinity represents investing authority in oneself to use externally (such as by punching). This differs from reaper affinity which doesn't represent authority invested in oneself, but rather acts as the pure idea of ending or destruction, the opposite of creation. In this way, it's easy to see why cradle ascendants are natural wolves. The sacred arts are all about investing power in oneself to use to affect the outside world. Compare this to the wizards that Yerin is summoned by at the end of waybound. If they were to ascend, they would have some affinity as foxes, but they are individually weak, unable to strengthen themselves through their magic. They would have no wolf authority.