imperious, wayward, empirical, and impatient [imperious = arrogantly domineering or overbearing]
improvident, incautious, prodigal, and thriftless
impudent, insolent, irrelevant, and officious
inadvertency, carelessness, negligence, and oversight
indecision, doubt, fear, and lassitude
indifference, caution, coldness, and weariness
indolent, passive, sluggish, and slothful
ineffectual, powerless, useless, and unavailing
infamy, shame, dishonor, and disgrace
infantile, childish, boyish, and dutiful