The skill style system is relatively new, and while I love the idea, I think it could be cleaned up a bit. With subclassing on the horizon, I feel as if now is the time to add some cohesion to skill styles. Take the Class Style Pack: Tamriel United that we were able to get for free from the crown store a little while ago. At first I was really excited about it, until I realized that each class only got 3 skills recolored. What's the point of using a blue DK style, when all of your other DK abilities are still fire orange. Skill styles have the ability to make subclassing more visually appealing, but I would love to see the Tamriel United class skill styles expanded, maybe with a Tamriel United part 2 pack or something. For example, let us turn all necro abilities red, not just 3, and they would seamlessly match the NB skillset - encouraging subclassing between the two.
My other hangup with the Tamriel United pack is the inconsistency in color names... it isn't a big problem now, but if more class skill styles are added, it will become very hard to sort through everything. All DK skill styles in this pack are called ice blue, all NB ones are lilac purple, all sorc ones are ruby red, and all warden ones are blazing orange... BUT 2 of the templar's are ice blue while one is azure blue. Similarly, 2 of the necro's are carmine red while one is onyx red, and 2 of the arcanist's are azure blue while one is soothing blue. It is especially easy to get the blues mixed up, and in general the cohesion is lacking with the way these were named.
Finally, I would love to see skill styles get their own tab in the collections menu, rather than being a sub-category within the appearance tab. It is very difficult to sort through the skill styles we already have, and this problem will get worse as more and more are added to the game. If skill styles were given their own tab, there could then be sub-categories for each skill line, making it very easy to see which styles you have available.
Call me particular, but I don't really use skill styles right now due to their inconsistencies. If the system got cleaned up a bit, especially in light of subclassing, I would be much more inclined to use and PURCHASE skill styles from the crown store.