I spent 3 days in Big Bend and really LOVED the park!
Hiked to Hot Springs and found this manmade pool by the Rio Grande where i could enjoy a nice warm river bath, the trail to the Balanced Rock is beautiful and quite, and the view is amazing. The best part to me was the Ross Maxwell scenic drive leading to the Santa Elena Canyon, where you can hike into the canyon via the Santa Elena Canyon trail (do it til the end), not easy to find but totally worth the detour, you won't regret it, it's mystical, i found a bit of Heaven there. Will go back to Big Bend!
A bit disappointed by the park. The excitement of my visit fell down quite fast. The area is not very impressive, but most of all, i slept at the Governors' Landing Campground and i had a terrible night, with the highway a few hundreds feets away, i've heard the loud noise of the trucks the whole night.. Maybe other campgrounds are better, i hope so!
The Lincoln Forrest is beautiful and the Apache Reservation is even more beautiful and well cared. At the end of october, the colors and the lights were amazing, the trees are majestic. Wish i could have spent more than a few hours there.