These cards are the generic attacks that all characters can use. They don’t cost a lot of CC and don’t deal the most damage, but they can be useful. For one thing, if an enemy avoids your Energy Wave, that’s only 12 CC wasted as opposed to 23 CC if you had used S.Kamehameha for example. It’s also not too hard to regain 10 CC and attack again, as opposed to gathering a lot of CC for a big attack that may be avoided and wasted anyway.
A character like Recoome can become very deadly if you upgrade his high Strength stat and attack with multiple Cont.Punches in a row. The same strategy can be applied to someone like Vegeta, who focuses mainly on Ki and can deal quite a bit of damage with multiple Energy Waves.
Cont.Kick is probably not as reliable as the other three cards, because it’s the most expensive one and its accuracy is somewhat low.