Watch out for dogs and potholes from Miles 27-32....

If you continue down Seagoville Rd. into Seagoville, you can catch Malloy Bridge Rd. to the west, taking you to Ferris, and can ride northeast up to Lancaster.  I did this from Forney last month.  It's about 20 miles one-way from your turnoff point this Saturday.
 
http://ridewithgps.com/routes/1165082
 
You can also continue further southwest on Seagoville Rd down to Combine, take a left on 3039 to Crandall and continuing on 148 all the way to Terrell.  Nice route...  about 25 miles one way from that same point.