In my opinion there is not much in the range of "driving to work" in Missouri you would want to live in with kids (and a .gov job paycheck, sorry Clayton/Ladue is probably out
).
It sucks living in IL because of the chicago state politics, but in So. Ill. it doesn't affect your day-to-day much in my experience. It might kill your pension some day, it might make your house impossible to sell in the future, taxes are higher, etc (macro level stuff-these are definitely BAD though!)--you have to make the call there, but I don't recommend it.
If I was dropped into the position of having a job in Collinsville, I would likely look toward Edwardsville, Troy, Highland/North of Highland areas. Maybe some rural spots directly south/southeast of Collinsville are nice, but not sure of schools. If you want more rural cow town, you can go straight east too. So it will depend on what you want to have, suburbs/convenience/small town/school/etc.
Don't expect to come and buy land, farmground around there goes for 12k or more an acre, so EVERYTHING is high.
Good luck in the decision, God I would hope the money would be huge (can't imagine that in a gov job)