Newer House on the plains- high wind and drafty in winter?

Getting advice from the neighbors is prob your best bet. See what works for them. You would think the builder wold have taken this into account when building the house. Maybe you can register a complaint with the builder and get him to fix it. 2005 is still a new home in my book. In any case, if you get snow where you live, you don't want to block all your attic vents as this can cause the attic to heat up, melting snow on the roof and causing water to run off and cause icicles and leaks in the winter. Fixing one problem can lead to another.