I mean that’s kinda the game. You’re a human, they’re giant monsters with godly powers. They’re bigger, faster, and stronger than you. All of them. Always.
Also, you move slower when you have your weapons unsheathed. Some weapons like Dual Blades or the Insect Glaive aren’t bad, but running around with an unsheathed Greatsword is intolerable.
This is also the game. Each weapon has its own sequence of attacks, and no, you can’t cancel most of them. Some special attacks have a cancel, but most don’t. You have to know your weapon’s combos and their timing, and then time your attack sequence in a moment of opportunity. This involves learning the monsters, reading their tells, thinking several moves ahead, positioning yourself to be able to capitalize on future situations, and being patient.
You can’t cancel because the game punishes you for fucking up.
It’s more of a puzzle game than a traditional 3rd-person action game. This game is to 3rd-person action what Ikaruga is to SHMUPs.