I don't think we should count kage's that we really don't know much about like 4th, 3rd kazekage 2nd mizukage 2nd raikage, ect ect. Cause we don't know much about them, and they must have been kage level for a reason.
Yea, tsunade herself might not have any ranged attacks that we know of, but.
1.) i don't really think kakazu can hit tsunade with any of his attacks, cause in theory tsunade should be a boss at dodging (from what she though sakura)
2.) she can close vast battle-distances pretty quickly, as shown when she just jumped up to madara and punched him, without him doing much of anything to retaliate
3.) The slug, you guy's aren't really taking it into consideration, i know the little acid it spits out isn't exactly the most op'ed attack in naruto, but it's nearly invulnerable to physical attacks, at least the kinda kakazu uses.