It comes down to personal preference
Flame Thrower - up close and personal
Mole Bomb - Movement and mobility
Old Woman - Pile Destroyer
Homing Pigeons - More Homing Weapons for long range
Sheep Launcher - best of both worlds, sheep for long distance
Mad Cows - tunnels and high damage
Holy Hand Grenade - meme, semi-unlimited timer
Super Sheep - long range, can be used almost everywhere