Minicrits on the umbrella and haste on the cane are both similarly powerful effects. Haste does pull ahead slightly due to the greater synergy it has with a majority of classes and weapons, though the Minicrits still have an advantage at farther ranges and in conjunction with explosives due to the removal of damage falloff, but require more coordination and skill on the part of the receiver to make full use of them.
The faster charge time on the cane, though, tips the scales too far in its favor, as being able to proc the effect more frequently just means your team can push up more often with an advantaged player. Even at its current 2 second shorter cooldown, it will naturally outpace the umbrella, so I think it should be removed from the weapon.