The smoke bomb is an amazing thing. I've been using it lately in a fairly counter intuitive fashion I like to call the batman. The batman is very effective for yellow and red.
To execute the batman do a move acton and attack an opponents space, fully commit to the first combat by mostly playing off the top so that your deck is depleted after you win the first combat and either steal a gang member with yellows leader or trigger one of reds mysterious benefactors. Then you simply smoke bomb out of the second battle and shuffler you discard back into your library.

For red you can trigger your MBs without worrying about two rounds of combat and you get to go "fishing" for scrappers by playing off the top, you also get the free "refresh" from the bombs shuffle.

For yellow you have a free action engine going, you get a move+refresh+recruit action all in one, and if you leave a disciple in your hand you can immediately draw through your deck after the smoke bomb and get all those rally the peoples again.

In other words the bomb friggin rocks.