Instead of Rattata, I’ll compare the two Raticate.
Alolan Raticate: Normal / Dark
As you see, Alolan Raticate’s typing is more offensive and Normal Raticate’s typing is more defensive. But due to both of them having poor defensive stats, the pure normal type won’t help. So, in typing, Alolan Raticate wins.
Alolan Raticate: Gluttony, Hustle, Thick Fat
Raticate: Guts, Hustle, Run Away
Normal Raticate wins because of Guts + Flame Orb + Facade, which is one of the strongest combos ever. However, if you are looking for a more defensive ability, Alolan Raticate might be a better choice.
Sp. Atk: 40
Sp. Def: 80
Sp. Atk: 50
Sp. Def: 70
So, Alolan Raticate is more defensive and Raticate is more offensive. It seems Alolan Raticate’s typing (Dark type STAB) and Hustle make it offensive, so Alolan Raticate is better.
Alolan Raticate is the winner due to it’s stats and typing!!!
But, however, be aware of Fighting Type that could outspeed it such as Swift Swim Poliwrath in rain, Primeape and Silvary-Fighting and OHKO it with their powerful Fighting STAB moves!
Hope it helps!