Okay so my thing isn't the best because lacking an actual pen and tablet atm. Also gonna be short and sweet buddy so ilu smooch smooch.
Right, first of all I love how you've done your crowd, it's a bit messy for me but it's very concept arty with all yo FDZ school style coming in. It's super fetch. I think it's overall pretty darn gewd as a concept.
Onto things I had issues with.
Value, I changed it to grayscale because the value is wrong on her for lots of reasons. One, where is the light source? I'm pretty stuck to whether it's infront of her, but then the crowd behind her is saying it's behind her. So I chose behind, and I then made sure to add a light source and use those beautiful fucking banners of yours as a means to add atmosphere and so therefore that depth you're lacking in. I then started fucking around with her values.
What I found was that 1) she has no range in values. Like, colour check it yourself, she's basically entirely on the top 20% for the top part of her face, which is then against a fairly lower value a background, making her look like a peice of paper. I see you noticed that because at some point you were all "dang man that armour just aint popping" and so you went full white on the highlights of her shoulder pad, and that then makes it more flat by removing any surrounding highlights pop. So I darkened her down a bit and I added contrast.
I basically did that with the background too to add depth but I mentioned that, (contrast is gr8 for focus yo, and so I made sure to pick a point in the page that brings you a focus to as opposed to just her and the head, and if you notice beside her, I tried to add a little focus or contrast to suggest some shitty little bunch of flowers, or even just more focused on grass, to then create triangulation within the composition which is the shit baby jesus is made of).
I just generally tried to add value and that's super hard on a laptop.
Also her anatomy if fucked up. She's a girl in full armour man, her torso is not that big and that armour should bulkier, try and think about how she would look naked and then contemplate how the armour would look on her.
Also I changed her arm a bit to suggest more foreshortening and also to try and give the head she's holding some pop too. Though i'm not going to lie I did fuck all to help on making htat the focal point because it's hard to do brush strokes on a laptop and you already put so much pop around her face that it's easier to just say that's the area of focus.
If I was you i'd make sure some sunly glare hits on the decapitated head and to add just generally a fuck tonne more detail to her and his face as well as the contrast because otherwise it's like having focal points within soup.
I really really love your work though more because you improve a fuck tonne everytime and hey you have the guts to show your work *kiss on cheek* xoxoxoxoxoxox