The spell would read as follows:

Superior Darkvision

2nd-level transmutation
Casting Time: 1 action
Range: Touch
Components: V, S
Duration: 1 hour

You touch a willing creature to grant it the ability to see in the dark. For the duration, that creature can see as if the area was brightly lit out to a range of 30 feet, treating areas beyond that as usual

The reason I want this spell is that, as discussed in the link below, most base races have darkvision, which makes the typical darkvision spell not as useful. The idea with this spell is that it would replace the normal darkvision spell.

What can or should be changed to make this a balanced spell? (Changing spell level, changing duration, adding concentration, etc.)

Ideally I'd want to keep the spell level as is.

See also: This answer to "What would happen if I removed darkvision?"

This spell should probably be 3rd level, not 2nd level

The issue right now is that as-written, this spell is strictly better than the Darkvision spell in every respect except for its range and duration, which is not consequential enough to keep the spell as a 2nd level spell.

It's not quite as powerful as a 6th level spell, though, like Truesight, which has a longer range and detects lots of other things than just allowing vision in darkness. So that puts a firm upper bound on the power level this spell should target.

Pros:

• Allows normal Perception checks in pure Darkness


• Has no Material Component (can be cast without a focus)

Cons:

• Lower Range (normal Darkvision has a range of 60', this has 30')


• Shorter Duration (normal Darkvision has a duration of 8 hours, this lasts 1 hour)

The heightened perception check range is very significant though. Normally, when detecting a hidden creature or object, having disadvantage on Perception would confer a flat -5 penalty to their passive checks, meaning a whole lot of hidden creatures, traps, etc. would be suddenly easy to spot with this spell. Normally, to gain that kind of perception, you'd need to use the regular Darkvision spell and use a torch or some other kind of light effect to at least bring the light level up to Dim. This spell negates the need for any secondary light source, which makes it superior.

I suggest that you ask yourself: Would I ever voluntarily take this as a second-level spell? If the answer is "no" or "probably not", then your spell is set at or above the correct spell level.

Comparing this to the existing Darkvision spell is probably not the best gauge, as it assumes that Darkvision is balanced at L2. Darkvision is probably one of the most situational spells at L2. Few players seem to take Darkvision as-is, at least until higher levels, when the cost of the slot and the spell known is negligible. If you're playing a human or halfling caster, you've probably got a cheaper way of dealing with your lack of innate darkvision than a spell known and a second-level slot. Even then, the spell's use is limited to Humans and Halflings.

At level 3, you can take this or something like Hypnotic Pattern, Plant Growth, Haste or Fireball. Your players have better things to do with their L3 spell slots than fixing their lack of innate darkvision.

It is unclear how this spell interacts with magical darkness, such as in the Darkness spell. This would be a major factor regarding whether this spell is worth taking because you can effectively give yourself full cover while maintaining vision, which is definitely worth a L2 slot. Some food for thought.