I do believe you'll enjoy Tyler SP. Tall pines, lots of shade and a really nice lake. They have made some changes since I was last there so I'll say little about the sites except that I found the ones they had to be very acceptable even before any inprovements. Park has a large deer population and watch out for the racoons! They think they own the park.
Isle du Bois Unit on Ray Roberts is also very nice. Not as much shade but some areas are pretty good. Really enjoy some of the lakefront sites. Good facilities and very well kept on our last visit. Park has a great sand beach for swimming and the lakes in Texas are full again (at least in this area).
Ft. Richardson is a nice park to visit. Lots of history that should keep you busy for a fair part of a day.
If you really want to see some balloons, I would strongly recommend the Albuquerque Balloon Fiesta. Here's a link for this year's event:
http://www.balloonfiesta.com/
Might be something to look at later.
Hope all this helps and you have a great trip!
Happy Camping!
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Turn Key, DW & Tilly, The Camping Boston Terrier
'03 Chevy 2500HD, 4X4, X-Cab, Long Bed
'04 K-Z "Durango", 275RK ("Sunday Haus II")
Twin Kayaks, "The Ride" by Wilderness Systems
North Central Texas, Where The West Begins!