Adorning the buddhas and bodhisattvas with pleasant flowers will enable one to possess the perfect signs of buddhas and bodhisattvas. B4 Rice and Incense Offered to the pleasure of the Buddha's nose, ie. Represents the pervasiveness of the Buddhadharma. The real incense offering is the practice of sila and samadhi. One will accumulate the good karma of such solemn offering.
Awakened ones can see with their wisdom eyes.
Darkness is ignorance and wisdom is brightness. Brightness dispels darkness and wisdom dispels ignorance. Offering lamps can help awaken one's innate buddha nature. Offering perfume is to purify one's bad conduct and defilements like greed, hatred, attachment, etc. and ultimately purifying outer phenomena till perfection. Temporarily it relieves the hunger of beings.