Such insightful replies. You’re great, people!
It took me a long time to get back here because, first, life got in the way, but I also wanted to test some of your suggestions so that I’d have something at least a bit substantial to say.
I tried switching to a night scene. I’m working on the outside in this hatching style I’m struggling so much to get the hang of. Please let me know if you think I overdid it—especially the moon. The thing is: now I feel like there’s too much light inside the car. I don’t want to put a light source inside it, as it will change the whole direction of light and shadows etc., but at the same time it is getting ugly if I just darken the rest of the inside, so I’m considering getting back to the sunrise and doing it in hatching style as well.
Thank you everybody who chimed in. If any of you have further suggestions, please let me know. I’m really needing some help here. No problem at all that some of you drew over it. On the contrary, it helped me a ton figuring things out and taught me some techniques and solutions along the way.

P.S. to end this already long response, in case anyone is interested, here is an explanation of the idea for the image:
I think the interior is more important, but I need the exterior too. The whole thing (this is a record cover) is dealing with the idea of longing for times past, so there’s a mixed chronology there—the car is from the 60s, there’s that little Nokia phone from the mid-2000s, the car stereo is current, there’ll be a sticker on the dashboard that can only be from 2019 or later etc. But on the outside the idea is that things get weirder, as that sidewalk in from of the car hints that it’s a specific place here in Brazil, but at the same time (time?! well, that’s the point I guess) that building on the right has been replaced by a new one in the 1910s. All this is to say that I have to somehow manage to make all this part of the picture, which I guess shows how inexperienced I am in this whole business… The fire extinguisher isn’t important at all. I was just copying from a picture of said car that I found and it balances the backpack, which is indeed more important. Finally, the rearview mirror is going to show very subtly a couple together in the backseat, just the bare minimum for you to understand there’s people there.