Some of the most striking, I have noticed...
Mild nitrate deficiency: smaller leaves, stunting
Severe nitrate deficiency: entire plant turns pale and transparent
Mild Fe deficiency: lanky, green growth with long internodes
Severe Fe deficiency: white, crinkled new growth with brown spots (necrosis)
High nitrate, low phosphate: longer internodes, more orange color with yellow splotches
Low nitrate, high phosphate: shorter internodes, very deep red color
(assuming Fe/traces are in sufficient amounts)