What size is that cage?
An adult ETB is suggested to have at least a 3ft x 2ft x 2ft. You seem to have the height but not the width. Also you need to have at least two perches but three would be better. The snake needs to be able to regulate itself by moving up and down the enclosure by moving to the different perches.
The analog gauge you have is actually pretty accurate but it is no replacement for have a IR temp gun. Keeping arboreal snakes they are incredibly valuable. You need to be able to know the temp of each perch so you know has the proper hotspot. A regular thermometer or even a digital one with a probe will not keep your keeping like a temp gun will.
The paper on the sides is a nice addition and should help the snake feel more secure.
If you are able I suggest you check out PVC Cages. That is what my GTP has been in since 2012 and what I just ordered my new ETB. I got mine the 3x2x2 with perches, led light, and rhp. I also got three greenery bundles as my first cage could use some pieces replaced. My total with all of that including shipping was $416. He sent me an email and said Im about 3 weeks out for delivery.
http://pvccages.com/
They make great cages for arboreal snakes and make keeping the temps and humidity a snap. You will also need a nice tstat for the rhp. For that I suggest Herpstat from Spyder Robotics. All four of my tstats are from them and none have ever given me an issue.
http://spyderrobotics.com/
Also I can not help you if you do not help me. By failing to answer the few questions I ask you make it harder for me to help you as I have to work with little information.
So again. How are you preparing your meals for your snake?