spur of the moment; no preparation at all
impromptu
prepared beforehand but not delivered well
extemporaneous
abundant
rife (rife with)
a fortunate accident
serendipity
smallness in number; not enough
paucity (paucity of)
pleasing, soothing, agreeable; sweet to taste
dulcet
lacking something needed or desirable
destitute
to run at the nose; to cry or whine; to speak or act in a whining manner
snivel
an abusive expression or speech
invective
a combination of incongruous parts; an imaginary monster
chimera
to present for acceptance; offer
proffer
empty boasting; cocky manner
braggadocio