So the chest diamond even as a negative space is an issue, they are iconically modern and aren't something that should be a part of an early crusader kit. So you will need to close up that gap.
What is your vest made out of because it looks like it is made from t-shirt type material which is also an issue.
Additional if you are going to go the mask route, you need a cowl not a hood. I would suggest attaching the edges of the hood you have to the mask so you get the nice cowl look that is seen with masked early crusader reference material.
As for the pouches the three ammo pouches are a bit to "modern" for an EC kit, I would suggest using a couple pouches similar to the fourth pouch you have on that belt, also early crusader kits generally have little to no pouches so you have a fair bit of wiggle room there as well.
Other than those things, the kit is coming together nicely, I like the sort of bone/shell look of your chest plate, and shins it is an interesting way to get that organic look, weapon looks good and the mask itself is solid. I would suggest weathering up your soft goods, as early crusader kits are generally speaking pretty rough and tumble
Anyway keep up the good work