Considering opening a art painting shop-for the public to paint in. With coffee smoothies too-?

Yes, I think so. But, "thinking" isn't enough. When I'm evaluating a business opportunity, I'll sometimes conduct a Focus Group. Basically, that's where you get a sample of people together (15-25) and do a face-to-face survey, exploring the opportunity. To get people to participate, I've had a lot of luck offering a good lunch (free, of course). Here's a good link about this.