I had to register for this thread because I live in Crown Point, Indiana. It's a cute small town, and not at all suburban strip mall hell--there's a town square with lots of festivals and the downtown area is nice and walkable with a library, parks, bike trail, schools, town pool, sports fields, small museums, shops, restaurants, etc. You're not too far from rural areas either, and the school district is one of the best in the state. CP is about 19 miles away from University Park, so maybe a bit far, but it's something to think about. I'm sure MMM wouldn't condone that far of a commute but it's really up to you.
Indiana does have significantly lower property taxes, and cheaper gas, lower sales tax, lower property taxes. However, most of what I know is comparing Lake County Indiana to Cook County Illinois and since University Park is in Will County (which has much lower taxes than Cook) I'm not entirely sure if IN would be significantly cheaper. License plates for cars are less in Illinois than they are in Indiana, but that's about the only thing I know that's cheaper in IL.
Dyer, St. John, and Schererville are nice towns too, but perhaps a bit more suburban/strip mall like. Schererville does have a small downtown area, but it's not very happening. You'd really just have to visit to see if they're the kind of place you'd like to live. I really think Crete, Illinois is a nice looking small town too that definitely doesn't have a suburban feel (more rural/small town). However, it has a huge problem with residents moving to Indiana (even the mayor admitted it) and the population there has been going down in recent years, I think because of the higher taxes.
I really like living in this area (I'm not from here originally) and would be happy to answer any questions you have. I don't know a whole lot about towns in Illinois but I can always ask some of my friends who live in those areas where the good places to go are (though I will say, their number is dwindling as many of them have moved across the state line). As far as being in the Chicago area in general, here you're far enough removed from it to feel separate if you want to (especially from all of the crime and high prices), but you definitely still feel connected to the city. It's close enough that it's convenient to visit for entertainment purposes and many people even commute in to the city daily.