Well on the looking older thing the only advice I can give is give it time. Build some muscle if that's what you want, I know working out seemed to help me pass more especially after I got rid of the fat in my face. Try wearing button down shirts instead of tshirts, very few young teens wear these. Wear slacks instead of jeans. That kind of thing on the wardrobe front has helped me, especially since in my line of work I am around high school aged kids constantly. It seems the more professionally I dressed the more years they tacked onto my age.
Personally I've given up on facial hair hah, it's just not in the cards for me. And honestly I have taught 16 year olds at work who have full beards...so yeah. A beard may or may not help you on the age front.
Your face has a lot of the same structure that mine had at about the same point in hormone therapy, I think you may get some more sharpening in your facial features. I did right around 18 months and at 2 years it's very noticeable and has helped me pass quite a bit. Running helped me slim my body fat down and I'm sure this probably helped with the general fat reduction.
For haircuts I'm not much help since I tend more toward alternative and different hair styles. I pass better with longer hair and like longer hair so I have an undercut with a longer than usual crown. So far this has been the best hair style for me, I get the length I like and still pass since it's mainly a man's hair style. Short sides and back, and normally tapered from side length to crown. Mine is usually shaved on the sides and back and then long, no taper (very drastic length variation). Short on the sides and longer on the top seemed to be the key passing combinations from all my past haircuts. Try styling products if you want, try combing your hair differently. I started combing my hair forward and to the right instead of the left and all of the sudden it seemed (back when I first did it) I passed flawlessly. It was pretty interesting hah. Maybe cismen are more likely to comb their hair to the right?
ETA: Oh and a side note about facial piercings (I did have them...snake bites, ears in several places, eyebrow and an industrial.) you might need to play with the type of jewelry you wear. I had the best luck with plain titanium rings, black (I passed the best with black), and studs. I've since retired all my facial piercings to look more professional, except for a single small skull stud on one ear. And sadly I hate to break to you but I started passing more easily and as older once I took out my lip piercings and again once I took the rest out, minus the single stud on my ear. The rest of my piercings aren't visible so I kept them. I know piercings are hard to take out, and I love them!, but I made the choice to try it. I've noticed that around here guys that have piercings are very minimalistic unless they work in a very artist field or tattoo shop. I recently got my tongue pierced and so far it hasn't affected my passing. There might be hope for getting more piercings later but for now I like passing easily and as close to my real age so it was the sacrifice I made. Try different styles of jewelry and see if it helps you out.
And also it helps to learn to ignore the masses if they misgender you. It's not your fault they're wearing gender blinders.
