D&D 5E Setting spell level for homebrew spell - advice please!

[Hawk Diesel]

For starters (setting aside the "paladin-ness" of obscuring one's face from your enemies) make it an Illusion, not an Evocation.

Duration should just be 1 minute per level. Or something that isn't Concentration dependent. This is a paladin spell that can/will clearly be used within combat. It really shouldn't be a concentration dependent spell.

I think as a 2nd level spell, it's fine with the following changes:

The light shining from your face obscures your identity. That's automatic, the whole time the spell is in effect.

Make the save or Dazzled for 1 rd (end of your next turn or whatever). But it can't be just anyone that looks at you. The light is shining off of your face. So a direct "line" or small conical effect, tops.

I would make it so that you can, intentionally, as a bonus action, attempt to Blind (for d4 rounds) a single individual you are facing, that can see you, within 20' (and fails its save. Dazzled, as normal, with successful save). Once per round, to one target.

And/OR, as a standard action, attempt to Blind all targets within a 10' long x 15' wide at terminus cone in the direction the caster is facing. Using this "active area attack" immediately ends the spell.

But not "everything looking in your general direction must avert its eyes or..."

Your recommendations seem more inline with a spell from 3e/3.5 than 5e. Duration of x/level, the dazzled condition, variable effect durations (i.e. 1d4 rounds), and facing rules are not used in the current edition.

I do agree that Illusion may be more appropriate than Evocation as the school of magic, but most official light-based spells are listed as Evocation. As for the concentration, there are many spells that are combat focused but still require concentration. Blur, the spell that seems closest to the spell-effect that @Lawmonger is going for, is concentration. Heck, Barkskin is concentration. Now whether that makes sense is a separate discussion around how concentration is handled in 5e. But if someone is trying to make a homebrew spell that is balanced, they have to consider where it fits in relation to other existing spells as they are.