元 drew a person with a stroke marking the head — the top of the body, hence 'first, origin, primary'. The head of the year is 元旦 (New Year's Day); the head of money is the 元, China's currency unit.
Prices in China end in 元 (spoken 块 kuài): 十元 is ten yuan. 元 opens things: 元旦 New Year's Day, 状元 the top scorer of the imperial exams, 元气 primal vitality — what you restore with sleep and hotpot. The Yuan dynasty took its name from this 'origin'.
A person with a big HEAD — FIRST, ORIGIN, and the unit of money.
元气满满 'full of primal energy' is how young Chinese caption their good-morning selfies — Han-dynasty cosmology recycled as social-media cheerfulness.