I like what you draw and I think you're making a good start at figuring out anatomy.
The one useful thing I feel I can point out is that most of your drawings are of slender people with angular faces. Which is nice and all, but it makes me wonder if you're able to draw short, fat people or boxy, muscular people too. Not everyone looks like a fashion model! It's almost like anime disease but I don't think you draw in an overly generic way.. it's just that pointy chins and slim bodies remind me of it.
As for your writing, I can offer a few observations:
You have to get rid of this stuff. It makes the prose feel rudimentary. You need to be economical with words and these are wasted space. Can you structure the conversation so that it's obvious who is speaking? Are we a third party or are we mainly viewing the situation through the eyes of one person, so that it is unnecessary to name her? Is it better to say
"Still dark outside, ain't it?" He exclaimed, leaning back on his chair. Agatha looked up from the cards and then looked outside through a window behind the man.
His gruff voice reverberated through the glassware.
"Still dark outside."
Eyes narrowed, she nodded agreement.
Maybe this is not what you want to convey about the characters, but it's shorter and cleaner to my eyes. It relates audio-visual moments rather than straight dialogue. You do this occasionally (he blows on his cigarette, the nice little diversion after that when she checks her cards) but not enough.
You sometimes have interesting scenes that are killed by overly technical writing.
"Blackjack, sister." He said, then took the playing cards. Afterwards, his thick and stubbed fingers distributed the next hand.
"Blackjack, sister." He began to shuffle, the glossy cards slipping through his stubby fingers.
Does this work as a kind of metaphor for his conversational victory? The idea that he might not even deserve victory? Is it a chest-thumping gesture that forms a part of his negotiation? What would it feel like to watch him, and would it matter that you'd feel that way? Try to make everything serve a purpose. Never just write he did this and that and it was adjective.
You violate a lot of these guidelines.
I think this is worth a read. Look at what you did wrong according to the article, and defend your choices from it. If you feel like giving in on any point, that the advice would
make for a better story, then do your best to wean yourself from these habits.
On the other hand, I think you establish a clear voice for these characters in the story. What they actually say to each other is restrained and careful and seems to convey a great sense of personality for such a short piece.