If you work near 170 and 270, then you are north of the airport, but the housing up there won't meet your price point. The closest to your price point, while still maintaining your 30 minute commute and staying with the schools and family friendly would be to go south and/or west toward Brentwood, Clayton, Town and Country, Ladue, Creve Coeur, Olivette, Chesterfield, Clarkson Valley, Frontenac, Huntleigh, etc. Would University City be an area that you would consider? It would also have homes at that price point.
I would suggest that you consider what school districts you want to be in, then search from there (while you might not have children in the schools now, that is a huge resale factor that you need to consider for long term appreciation). On my website, I have links to the State of Missouri website and several national websites that discuss school districts and how they compare to each other and how they have done on the state testing profiles. You can find those at http://www.YourSTLHome.com.
I would note that your initial search puts you in the Ladue, Parkway and Rockwood school districts, all of which are excellent choices and have great appreciation for resale purposes. Those areas are also noted for being very family friendly.
One consideration, whether you are looking in St Charles (where the homes are a bit more likely to be newer at that price point) or in St Louis county (where you will find some newer homes but more older homes at that price point) is to consider what amenities are important to you, then look to see where you can find them. Keep in mind that names change, so while they may call it a "hearth room" now, it might have been a sitting room with a fireplace 40 years ago.
As with all the other agents, if you would like assistance, or have questions, just contact me. I'm here to help (if I weren't I wouldn't be answering questions on Trulia!)