They were being a bit harsh, but you are there complete oposite. This is no where near a 4/5, giving someone that because you feel bad does more harm then good. And if you meant that rating then... =/ go check out the legendary terrain thread.
Fiery / red terrain are pretty hard to pull off looking good, and you being a beginner isn't the best place to start. But as for some constructive-criticism:
-More & better thought at tile variation: As of right now there are 3(4?) tiles in the screen shot total, and there all in huge separate chunks, mix them up in a manner that makes them look good (this takes practice to get good at, or just a good eye =)).
-The fog is a bit strong, you maximize the picture and it is a slap to the face with red. Just tone that down a bit, or use some custom lighting etc. to achieve the effect you want.
-The random fire-spam does nothing but makes most people want to down-rate your terrain =/, you really have to be careful with that. Maybe just done it down and put it in places where it looks like there would be fire coming out like a fissure etc. instead of just flat barren ground.
Goodluck on improving man =)