Can the player freely move horizontally while they are midair (air control)? If so, I would simply apply an appropriate amount of vertical force to get the player's feet above the platform and let the player move horizontally onto it.
This would give the player more control over the character and open up more movement options - For example, if the player (while hanging from a ledge) wanted to jump, shoot at something on the platform, then fall back down and re-grab the ledge while the projectile traveled to its target so as to dodge any projectiles the target fired back at the player. Such a tactic might make for an interesting boss fight strategy.
