Heedless of the consequences: audacious. (Merriam – Webster)
Done in haste without regard for consequences: Rash. (Merriam – Webster)
Full of fresh raw vitality. (Merriam – Webster)
Impertinent; impudent; tactless: (Dictionary.com)
Hasty; rash; impetuous. (Dictionary.com)
Energetic or highly spirited, especially in an irreverent way; zesty: (Dictionary.com)
If you describe someone or their behaviour as brash, you disapprove of them because you think that they are too confident and aggressive. (Collins Dictionary)
(of people) showing too much confidence and too little respect. (Cambridge Dictionary)
(of clothes) too bright and colourful.(Cambridge Dictionary)
Slide player. Brash.
Why Being Brash Can Be Bad.