Serious or straight forward could be my picks
Serious smart ...
Upbeat,humble,wise,smart, serious etc......hope this helps
Silly
The word silly has over many centuries taken a fascinating journey through a range of evolving meanings. Silly did not originally refer to the absurd or ridiculous – in fact quite the opposite. The word derives from the old English word seely, meaning happy, blissful, lucky or blessed. From there it came to mean innocent, or deserving of compassion, only later mutating this sense of naive childishness into a more critical, mocking term, signifying ignorance, feeble-mindedness, and foolish behavior - the meaning we know today.