would be a legendary thingy and unbalanced af
does a ton of ranged damage but melee is pretty useless since everyone probably has a ranged explosive weapon
Compared to other rare weapons I'd say it's pretty balanced. The chargeup for the skull is a second long, and I think it would definitely be a challenge when dealing with fast moving and aerial targets. The skull also has a relatively short lifetime before it explodes, so you can't get long range snipes with it very well.
The main thing I found that it works well at is sustained battles, where you can take advantage of its large, high-damage explosion, hitting people through walls or around corners if they're camping. And, of course, when you do hit your target directly, it's an instant kill. The melee attack is also suprisingly useful as a backup, because it's really fast, has a lot of knockback, and deals enough damage to reliably kill them with just the skull's blast radius when you follow up with a shot. Just don't use it as your primary attack.