Mystic Mondays is pretty affordable and has a colorful gradient style. Good for Instagram readings.
Thoth is a pretty cool style and one of the more recognizable decks, next to the original RWS.
The Spacious Tarot is another option, watercolor style, more minimal. I use it for shadow work sometimes. And if you want pastels, look at the Dreaming Way deck. The art has this soft Korean influence.