A couple thoughts on establishing "balance points" for assigning a level to telekinesis:
Breadth Not Depth: 5e's
telekinesis gives more versatility than AD&D – it allows you to move creatures (not the case with AD&D's version) & it gives you fine motor control over things like tools. However, it has a little less versatility than d20 telekinesis.
But maybe that versatility could be broken away into other spells/powers, allowing for more "depth/power" to what each telekinetic-themed spell/power does.
For example, 5e's catapult is pretty similar to the "violent thrust" option of the d20 version of telekinesis.
Actually, regarding the comment about the Telekinetic feat's shove-at-range being weak... the d20 telekinesis spell had one of the options being "combat maneuver" which is almost what Telekinetic gives you (d20 has longer range & allowed you to grapple/disarm, whereas 5e is limited range shove but it's only a bonus action). Maybe a better description than "weak" would be that it's "circumstantial" – in the right environment / context, knocking a creature prone or pushing it off a ledge is awesome.
Falling Objects May Persist: 5e's telekinesis persists even if you drop an object on a creature, allowing you to drop multiple objects (or creatures) over its 10 minute duration. In contrast, in the AD&D version if you launched an object at a creature the spell ended (but damage was capped at 1 point/caster level).
...However, 5e AFAIK has still not codified how much damage a falling object deals, so without an agreed upon norm the exact power level of telekinesis is up for debate.
Party Flight. 5e's telekinesis can also be used to allow the whole party to fly on a hovering 1,000 lb object – same duration, same concentration as the fly spell, only it works for the whole party and it requires the caster's action to move at a slower speed. So if you're looking for reducing the level of telekinesis but maintaining this "party flight" aspect, bearing in mind what it does in comparison to 3rd level fly spell is important while balancing.
Perhaps a good rule of thumb for balancing telekinetic-themed spells/powers is "the bigger it is, the slower you move it"...which is how the
catapult and
telekinesis spells are differentiated now.