Argonian does not provide anything useful regarding passive skills to either class. If you choose argonian, don't do it for effectiveness, because the best passive you have is the poison and disease resistance, which can be a good thing in PvP against bow users.

http://elderscrollsonline.wiki.fextralife.com/Racial+Skills

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That being said, it is fair to play Argonian as racials only matter, if you care about having your name on the top list of weekly leaderboards.

If magicka build:
Sorcerers are good at long ranged attacks, but the rotation of your skills will matter a lot and it is a bit harder to play at endgame content.

Nightblades are close to mid ranged dps mainly, and their rotation is a bit easier to pull off than sorcerers. Basically they require less skill.

If stamina build:
Both classes are good and have good sustainability of resources and buffs to dps, however much of your gameplay will depend upon your weapon skills.