1 feat, 1 mutliclass, 1 invocation, no resources ...If you pick up a feat, and three invocations, a multiclass and a consumable resource you deserve to get something good.
But the truth is, a range of 1200 feet is pointless unless you also have telescopic vision. It's further than you can see, and a lot longer than any dungeon corrador.
and it's around 360 meters - that's length you can see in the wide country or sky, and with spellsniper you have no limitation by length an ignore 3/4 cover. Just depend on what adventure you play.