Pick your Pokémon before your mug style
Pikachu is an obvious place to start, but the mugs go well beyond that. Charizard brings a bolder look. Bulbasaur and Squirtle point to the starters. Eevee appears as a regular design, in evolution graphics and as the inspiration for more unusual mug shapes.
Jigglypuff, Gyarados and Poké Ball designs offer even more options. So the character may matter more than whether the mug is simple or more detailed.
Standard, 3D or heat-changing
A classic mug lets the graphic do the work. 3D models make the shape itself part of the design, like the Eevee mug. Heat-changing models add a visual effect when the temperature changes.
That gives you three quite different mugs featuring the same favourite. A standard mug keeps the design clean. A 3D mug makes the character more tangible. The heat-changing version lets the design change as you use it.
Character, shape or effect?
The answer settles most of it. Start with the Pokémon if you already have a clear favourite. Start with the mug style if the shape or effect matters more than the character.
To see the full range, browse Pokémon. More cups and mugs are under cups and mugs.