Careful thought is consideration.
consideration
Consideration
thought
It could be concept, or thought.
Used in this context, the word "due" means "after careful thought and deliberative consideration given to the matter at hand."
One option is pensive.
The word careful is an adjective. It means to be full of care.
lies
The C has a hard sound in the word careful.
glib
Synonyms for cautious: watchful alert safe careful
The word "fastidious" means attentive to detail, or to cleanliness. The word "punctilious" means showing attention to detail, or to behavior.