A recent post at Astros Daily described Morgan Ensberg, Brad Lidge, and Jason Lane as the three most disappointing Astros in 2006. While it's true that none of them have had great years, I believe that there is reason for optimism for all three:
Morgan Ensberg is only hitting .229, but he's drawn 92 walks this year and his OBP / SLG is 389/458, good for an 847 OPS , which ranks 7th among National League 3rd basemen (behind Cabrera, Atkins, Wright, Ramirez, Rolen, and Freddy Sanchez). All this with a wrist injury that killed his 2nd half stats.
Jason Lane is kind of a mini-Ensberg - he's hitting .210, but his OBP / SLG are 328/404, which gives him an OPS of 732. That's not too good, but it's better than Preston Wilson, and it's basically as good at Aubrey Huff. Lane is better than a .210 hitter, and if his batting average rises next year and he keeps his patience, he should be a decent corner outfielder.
Brad Lidge has had some brutal games, and his 5.21 ERA and 1.43 WHIP are pretty ugly for a closer. But he's still struck out 94 in only 65.2 innings. His downfall has been his control - 32 walks in that same time span. But he's still giving up less than a hit an inning, and he can cut down on his walks, his strikeout rate is still awesome enough to make him a good closer. I think he can do it.