Things to consider when building an ironkin skewed army?

Hello, I'm currently starting my Votann army and am starting with the maelstrom box, the land fortress, and 2 boxes of steeljacks (so 12 total) and am curious where I should go from here.

My goal is to keep things near exclusively ironkin since I wanna paint a bunch of random stuff on their visors and like the big chunky guns the steeljacks have. At the same time I don't wanna make my army too spammy, and am trying to figure out units that compliment what I've already got, while also maybe investing in stuff that plugs up the holes that may come from playing a skew list like this.

I'm also really curious if anyone has any good places to look for ironkin helmets for the rest of my army, since I kinda wanna go for a CIS sort of vibe.