Implicating karate_gi -> dougi.

Reason: The karate gi is a type of dougi.

Done

Sorry to bring this back up.

IMHO this should be a Tag Alias, not an implication.
e.g.
Tag Alias:
Aliasing karate_gi -> dougi.

Do you have a better reason other than your humble opinion?

Is there a good way to visually distinguish what is specifically a karate gi from other dougi?

If so, then the Wiki entry for it should be updated to reflect that info.

If not, it should be an alias.

IIRC a karate dougi is made of thinner material than e.g. a judo/aikido dougi.
So, in images, no; I don't think we'll be able to visually distinguish.