While iPhones are sleek and stylish, the only thing that they are replacing are convergent previous technology devices without much stylistic precedence (unless you count the late 90s early 2000s "slightly ergonomic plastic" as a style) so nobody puts up much of a fuss. The Apple Watch is clearly an Apple designed product and it serves its function, but its replacing what has long been a style accessory with its own traditions and norms (particularly roundness), something you wear on your body and is visible to others at all times. When I see an Apple Watch, I don't think "Cool, that person has a smart watch.", I think "That's an ugly watch.". Round watch faces at least return to the classic shape.
My ideal smart watch would be round with mechanical arms and a mechanical crown, but with a color eInk dial/face with a high refresh rate (I'm not sure if there is current eInk tech which meets these specs yet). I do not want to look like I'm wearing a compass on my arm, though.
(I got curious, this is similar to what I'm describing, but still way too large and not quite the same: https://www.indiegogo.com/projects/gligo-e-ink-smartwatch-ha...)