Kricketot -> Kricketune
Tier: C or D
Availability: Very Early
Stats: Below Average
Movepool: Decent
Kricketot, despite having Bide as its first offensive move, is easy to train through switching out or using Struggle Bug, which it gets at level 6. Players will not have Kricketot for more than 5 battles.
Kricketune's Technician ability, alongside STAB Fury Cutter, make it a force to be reckoned with early game. By spamming Fury Cutter, Kricketune can easily sweep the first two gym leaders (provided that the attack doesn't miss and Kricketune is leveled appropriately). After that, however, Kricketune becomes outclassed by other bug types as well as other Pokemon with Technician and better movepools (after the second badge, Mr. Mime outclasses Kricketune as a Technician user.)
Overall, because of its immense usefulness early game, this Pokemon should be C or D tier, but no lower than that.