More citadel determinism pls.

I've done probably ~300-400 maps at this point, and I've yet to see an Iron Citadel. I'm not sure if I'm just unlucky with the seed or what, but for the last 100 or so maps, I've been going in a straight line pretty much, trying to get as far away from the 1st point, and I'm still yet to encounter an Iron one. So far, I've only encountered 3 stone ones and one bronze. While I understand they need to be relatively rare, I wish there was at least some determinism for the first of each kind so that I can progress through the quest and have at least one attempt at Arbiter without having to buy a missing fragment via currency exchange for 1.25 div (which still doesn't solve the unfinished quest issue).