Firebolt - randomly excite a bunch of molecules in front of you.
HMMMMMMMMMM, I WONDER WHICH IS HARDER TO DO?
At the College of Winterhold, Colette Marence (the Restoration trainer) is looked down upon for studying Restoration, an ‘inferior’ school of magic. But why is restoration regarded as inferior? I’d say restoration is among the most impressive schools of magic, if not the most impressive, simply because the mechanics behind a healing spell are just so complicated. Also, the non-healing parts of restoration have much in common with alteration (ward spells) and illusion (undead fleeing spells), and neither alteration nor illusion are considered inferior.
I’d say destruction is the least impressive simply because the explanation behind a destruction spell like firebolt or ice spike (simply de-excite the molecules) is just so simple.

This is marked by the decrease in versatility of the interesting spell lines (Alteration, Restoration).