One mistake I see players make is milling the wrong player
But don't forget these
When that spell or ability resolves, Dovin's Veto won't be countered, but any additional effects of the countering spell or ability will still happen
9 Aerith Rescue Mission Climbing All 59 Floors As the name implies, Tseng and the Turks have captured Aerith, and Barrett, Tifa, and Cloud are on their way to save her from their clutches
Provoke the Trolls Okay it's a nuke that can also be used to give a creature +5 damage, and could have some hilarious upsides, like with Brash Taunter and Stuffy Doll, but 4 mana is probably too much
Kenrith gives the massive advantage of activating abilities of all colors and effects depending on your need, including paying to give all creatures trample and haste