I don't have a huge experience with other cities, but for many of these, I'd throw out a suggestion for the St. Louis metro area (including a few towns across the river in IL)
Scenario:
---House will be purchased for $600k or less
---Cute, quaint towns are nice
---House has .5 acres or bigger lot
I imagine that in 2 years, even with a modest housing recovery most of the areas of the country would still be able to easily fit the bill of a $600k house on 1/2 acre+. You could get quite a lot of that in the St. Louis area (suburbs in the West County part, especially). Although if you're looking for cute, quaint towns, you could also consider Florissant, on the North edge of St. Louis county, dating back to the late 1700s (?)...or perhaps cross the Missouri River in St. Louis to go into St. Charles, which has been growing over the past 20 years but still has some 'smaller town' feel to it.
1. Within a 40 minute drive to a city with sports teams, restaurants, performing arts, and concerts
2. Weather not be extreme in the winter
Between the baseball Cardinals, (lousy) Rams and the (occasionally decent) Blues, you have 3 out of the 4 major sports teams. The periodic concert (both Pop and other genres), the St. Louis symphony, as well as a few civic symphonies and college music school symphonies (both free!
).
But you'd need to clarify what you mean by "not be extreme in winter". St. Louis might get 2 or 3 snowfalls, each maybe 2". Nothing extreme at all, although once every 6 or 8 years, you might experience a 6" snowfall. For a 2-3 month period, nightly lows might be in the teens/20s, with daytime highs in the 20s/30s. It's definitely winter, but not like farther up North where your snowdrifts are taller than you.
1. Fairly conservative people
2. Trees and forests near
5. Within 40 minute drive to an ocean or large body of water
1. Check.
2. St. Louis has quite a few county and state parks, along with some rolling hills as you head West/South out of the area. A popular thing is to drive for 30-60 minutes out to Hermann or Augusta (or South to Ste. Genevieve) to visit the 30 or so wineries. Great views at the wineries, some have a few decent vintages, spectacular to see the trees changing color in the fall. All around good times.
For water, there's the Meramec and Missouri rivers for a little recreation, or the 26,000 acre
Lake Carlyle in Illinois (about 50 mins from St. Louis), and the 320 acre
Creve Coeur Lake ...didn't know if these would qualify for "body of water"
The St. Louis area is a fairly large metro area with tons of things to do and see, while also offering a modest overall cost of living and not too much congestion with traffic and crowds.