I like the one with the green fields. Looks pretty distinct and I like something that captures the rural parts of the state. We are not just #Chicago! it so has some good subtle symbolism.
I think the Sesquicentennial one is fine. And the one with the gold star towards the bottom is okay (and easy to recreate).
Any with a big I or the picture of #Illinois or Lincoln should be banished to a dark place. I would rather keep the current one than take those.
What do you think?