You got some amazing feedback there! I'm a beginner myself so I don't know if I can add much besides the elements given I'm on Marc's course. I love the sense of scale you have here; the towering gate and the motion of implied lines leading into it. You really get a sense of the sheer size of the thing, you're positively drawn to the man and gate itself through the interaction between the two, and it's dauntingly beautiful! I like how the flags and swords suggest some long history in this environment, and it's definitely implied through the texture of the cracks at the top of the gate itself, and there's just enough form to accredit it further, and the shape of the mountain doesn't detract from the focus, good use of space. Was it possibly Lord of the Rings inspired? It reminds me of the Gates of Mordor for some reason (likely again the scale represented). I wish I could even be half as this good.
Sorry if this was unnecessary or late! But I like this piece a lot 
