Striders balance thier dagger and shortbow skills.
Rangers focus on longbow skills. Several of the bow skills that the Strider has are greatly improved if you become a Ranger. This comes at the cost of being unable to learn some of the Striders late game dagger skills.
On a side note, Assassins develop diffetent skills in all of the 4 weapons they can use. Also one of the sword skills is a game breaker against large bosses with vulnerable weakpoints, such as Dragon-family foes.
And Magick Archers are in an entirely different league compared to the other range classes, simply due to that the magick bows they use dont do physical damage. Theyre also quite hard to get the hang of, as theyre skills all require a large amount of stamina.
However the most important thing to remember is that all classes are equally viable.