I agree with Zincubus. I would get two hides to replace the half logs. Either the style you posted or the style Zinc posted will both work, just a matter of preference. When it comes to size, you want something fairly snug to make your snake feel secure. Ideally, they like to be pressed up against something when they can. Basically, if they are covered from as many angles as possible, they can't get eaten. Their primitive brains (though there is much debate on this topic) don't know a whole lot besides eat and don't get eaten. So feeling secure and safe from being eaten is very important to them.
Your water bowl looks good to me, as well as the plant/hide. Just be careful with those style hides, it can be extremely difficult to get the snake out if he/she gets stuck in there or doesn't feel like coming out.
A quality thermostat is very important, probably the most important thing you will buy.
A decent digital thermometer/hygrometer is important, they dial style stick-ons are wildly inaccurate. An Accurite from Walmart is under $10.
A temp gun is also extremely handy.
More clutter will also help to make your snake feel secure.