When I see magic shows, I like watching them from the back of the room. You learn a lot more about how to perform from a bad seat than you do a good seat. In theory your show will play to all areas of the audience and play virtually equally. I get that some things will automatically be harder to see from different parts of the audience by nature of distance, like a jumbo card will look jumbo from the front row, but smaller from the back.
When watching a magic show from the back, it makes you aware of what you can and cannot see. For example I personally can’t read a normal playing card from about the 10th row. What does that mean, someone in the back of the theater doesn’t know what it is. How do you overcome this? Use jumbo card, use low vision cards, make the card with a big X???
Then colors of props start coming into play. Having a prop that “pops” due to contrast
between what you wear or the background becomes important. I’m not saying all of your props have to be
neon colors, but it’s important for you to be aware of what’s visible and
what’s going to disappear.
Start watching shows from the cheap seats and you’ll soon realize most magic
shows are too small!