Hi Gloria! Welcome!
Here are my opinions on your questions-
1. It times time to make your first sale. Mine took 3 weeks, and even after that it was quite slow. For many people it can take months. You are right, summertime is slow for me, too!
2. I am beginning to branch out at different sites. I just opened a shop at storenvy.com, which is free. From the research I've done, Etsy seems to be the best site because of the amount of traffic it gets. I also have some work in local art galleries. It is challenging if you have items listed in more than one location- I have to call the gallery right away if a painting sells on Etsy and have them take it down! Probably better to only list it in one location, but if you really want them to sell, it's worth the effort!
3. I've done treasuries myself, doesn't seem to do much for me. Being in treasuries got me lots of views and faves, but (I don't think) any sales.
4. To drive traffic, just stick with it. Market on social media (fb, twitter, tumblr, pintrest, etc), and work on building a following. Your traffic will build slowly but surely.
I've written an article about things I've learned in my first 3 months of Etsy selling, which may be helpful to you:
http://paintspirationart.com/how-i-built-a-successful-etsy-shop/You have a cute shop! Best of luck to you :)