Sure Climber/Long Jumper: If you really want to be an awesome climber or jumper, it seems like Skill Focus: Athletics would give you more bang for your buck.
Weapon Focus: Decent, but Dwarves and Eladrin have a racial feat that outshines it, at least in Heroic tier. Others will probably find more useful feats to fill their slots.
Astral Fire/Burning Blizzard/Raging Storm: Hey, it's like Weapon Focus, but only applies to a few of my powers! Also, the statistical prerequisites are all over the place; there really seems to be no rhyme or reason to them, except perhaps a general "Screw the Wizard that tries to build a theme" theme. If I was a DM, I'd probably house-rule that these feats have no prerequisites. Then somebody might actually take them. Maybe.
The Majority of Channel Divinity Powers: Some are truly awful. Ioun's Poise? +5 to one ally's Will for one turn? "There, now you are probably somewhat safe for a short while provided the enemy uses a specific attack against you on its next turn, and only its next turn. Probably." Yeah, that sounds like a good use of an Encounter power, right there. Right on par with Turn Undead or Divine Mettle. Uh-huh. Sure.
Linguist: Love it from a flavor perspective. But I never end up taking it. Why? Because I can't come up with a reason why my character should spontaneously learn three languages!
Mounted Combat: Like the poster above said, it's possibly good, but not in Heroic tier. It's a tempting one to take with retraining, though.
Alertness: Negating combat advantage if surprised doesn't seem to come up enough to be useful. I'd rather take Skill Focus and get an extra +1 to Perception, thanks.
Anything That Gives a Situational Bonus: Dodge Giants/Defensive Mobility/Combat Reflexes/Dragonborn Frenzy, etc. I personally avoid these, because I'm sure I'll always forget the relevant bonuses when their rare circumstances finally come up. That's just me, though, and me knowing my own limitations as a player. I'm sure some are quite useful, if you can remember them and put yourself into situations where you'll use them. Nimble Blade's the exception of course: Rogues are always seeking out CA, so its circumstances are far from rare.