First of all, lovely violet! I love the ones that have the darker "eye" in the middle.
Your question has several possibilities. While I am sure that light can have something to do with tight crowns, as well as certain pests/viruses, I've found that there are a few other factors as well. If you're concerned about pests and viruses, you can bring some of the leaves to a lab for testing.
Temperature: if your African violet lives in a colder spot, such as a windowsill in the winter, it may get a little bit of scarring on the leaves and a tighter crown.
Needs a good repot job: I've found that the health of the plant is affected if I am late on a repot job. This includes how the leaves are shaped and how the crown looks. While some plants will survive for years without the repot job, some succumb to
root rot if they're not taken care of (don't ask me how I know about either). Soil quality isn't just about nutrients. It's also about how aerated it is. With time, soil in your pot is packed and breaks down. That is one reason why you need to repot.
Genetics: There are some that just grow like this, regardless of what you do. You can train the leaves but the new ones will grow back the same way: up and tight. I have one of these varieties.
Feel free to ask more questions. We have a lot more information on our
Facebook page: The African Violet Museum.
Jana Gerardi