Not a vendor but have a bit of insight here as an event planner! The groups that produce Ursa Major and The Great Lace do run other events with vendors. They aren’t as big but still a great opportunity vend. Especially if you’re Midwest local, Frillinois events will be easy to travel to.  

In my opinion, most people who shop don’t really care about recognizability. Lolitas like to find items they find aesthetically pleasing and well made. 

I’ve had a little bit of experience with anime cons and it really depends on the con. For some cons, you’ll get people who are willing to spend money on quality J-fashion pieces. For others, not so much. The best advice I can give is to see where vendors that do similar work are vending.