This should be a second-level spell
You've carefully worded this spell so that it's really hard to use it offensively. It's quite difficult to use this to drop someone off a cliff, or into lava, because they get to choose which space they appear in. If you use it on an enemy, you've also placed yourself with melee range of them, and you'll provoke an attack of opportunity if you move away.
(We can make it harder to use offensively by including some text about "arriving on a surface capable of supporting it". The 3.5e conjuration school uses text like this.)
You can still use it to pull your ally out of an awkward spot, which is nice -- but the original misty step was an escape spell, and this misty hook variant isn't an escape spell any more, and I think that's a fair trade.
(Also, this is a spell that promotes teamwork, and I like it when characters use spells like that at my table!)
If you can get past an opponent's saving throw, for a second-level spell slot you could hit them with blindness or levitate or hold person. I think moving them next to your character is in line with those spells.
For the friendly version of the spell, I think it actually should be a bonus-action spell as well, so that you don't blow your whole turn on pulling your ally out of a sticky situation.
2nd level conjuration
Range: 30 feet
Casting Time: 1 action or 1 bonus action
Choose one creature you can see within 30 feet of you. You teleport them to an unoccupied space of their choice within 5 feet of you. They must arrive on a surface capable of supporting them; if there is no such space, the spell fails. If the creature is willing, this spell uses a bonus action; otherwise, the spell uses an action, and the creature can make a Wisdom save to avoid being teleported.