i think the only competitive red right now is red/green (called archer).
Its also the cheapest tier 2 (or better) deck possible afaik.
The top ones that are a bit more controlled usually use a ton of legendaries with high magicka costs bombs (mostly purple with ramping magicka but there are also some mage control).
Yellow seems to be all over the place with many archetypes.
Blue also has some combo spells-to-face for kill if theyre not built for control.
Again, im still a newb. But a newb with almost 300 games now