There are great designs on the market already. The typical smart watch can be seen more as an extension to your smart-phone than as a standalone device.
Depending on how you blend it within your own lifestyle your new smart watch can be a anything from a most-useful gadget to complement your android experience or it can turn into a nuisance.
Be careful there. Better try some models prior to buying and by all means have a reason that justifies buying it in the first place!