However, you could use near alliteration with words like:
* Colossal: This creates a strong visual and auditory link, highlighting the potential consequences of carelessness.
* Casual: This emphasizes the lack of attention and thought associated with carelessness.
* Clueless: This highlights the obliviousness and lack of awareness that can accompany carelessness.
Ultimately, the best choice depends on the context and the specific meaning you want to convey.