I read some articles about the game and wondered who made the graphics because it looked really good. It's great to know that it was made by someone I know more or less. Thumbs up for that great job. Now I am really thinking about buying it to see the art together and in action.

Maybe you should also start with something small fist, it's better to do small things first because it takes less time than a big piece. Pixelart usual works with small sizes, every simgle pixel could be an important detail. You should try to make your face with a height of about ~64px

The arms use more light than the boots, so there is no reason why not. You won't remind it if you aren't exactly looking how the color is distributed. The arm could even be a little brighter too, more like the face.

If it comes to correct perspective, the view angle should also be  alittle bit higher than it is at the moment, but this would affect the whole sprite but if you aren't really experienced with doing things at your own from scratch it's easier just to edit the head.

I think the tileset is in comparison with the char to saturated /or the char is less saturated) and the char gets lost because he is really small.

I think you used fire emblem as reference. The problem is that it's a frontview perspective. The easiest thing you can do is to rearrange the hat, the rest don't really needs work iif it comes to perspective. The bigger problems are the colors, you used much and some of them quite ugly. I don 't know exactly what you are going for, but if it's the main hero and no tactical rpc the char should definitely be bigger, get a more interesting color sheme and he should pop out more.

I edited the perspective (as easy as possible) and the position of the shield. I also rearranged the colors a little bit, not much because I don't know your goal.