Ideas to Improve YOUR Idea
1. Yes, to be honest, I think it should freeze the troops in that area, but not freeze all of them. That bomb could freeze 50 archers and it would be unrealistic to have an idea like this ruin your entire attack. There should be a limit to how many troops it could freeze at one time.
2. If you continue to pursue this idea, why not have air freeze-bombs as well!
3. This idea is good, but not perfect. I recommend considering the idea that troops frozen cannot be damaged while frozen. This would force app users to put the bomb in spots where a lot of troops would be attacking instead of having it on the outside of the base where it would be wasted. If a giant freeze-bomb froze all the distraction troops (Golems, Giants, Hogs, Dragons, Pekkas, Lava Hounds, etc.), then the defense could immediately focus on the troops that are doing the most damage (Archers, Barbarians, Wizards, Minions, Valks, and Witches).
4. Some troops should be immune to the bomb (Wallbreakers, Witches maybe?).
Other than those four ideas, you may have something! Keep up the good work.