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The thing about software is that it is a slave to the 'best' route, even if it's only slightly better than some other alternative. In your case there is another route that is only 115 miles longer (out of about 1800) that does exactly what you want. Take I-78 out of New York and then hook up with the Pennsylvania Turnpike at Harrisburg. Continue on I-70 when it leaves the Turnpike southeast of Pittsburgh and take that to St Louis. From there, I-44 will take you to Oklahoma City and the junction with I-35 for the rest of the drive to Austin. Clearly, the beginning and end of this route3 will be familiar to you, but the bulk of it will be new road. So get out a good atlas and see what's along that general route that might appeal to you

AZBuck