赞! It means awesome. You could also use 真赞! which has the same meaning.
And me and my friends often use 屌爆了, which mainly used among young people oral language and Internet discussions, the text representation is not standardized, someone write as 碉堡了, when we (me and my friends) use this word, we roughly mean "awesomeness explodes", though it has many other meanings. 屌 and 真屌 is also valid and used.
For "wicked" and "sweet", above words can be very suited sometimes, but not always, since "wicked" and "sweet" have so many meanings. "Wicked" is more close to 屌 and "sweet" is more close to 赞.