Frankly, length doesn't matter much (or at least that's what your wife told you).

The way a cigar smokes is largely determined by the ring size (width).

A 7 inch lancero can take as long to smoke as 5 inch robusto, but they smoke differently. Pick what you like to hold in your mouth, which you prefer as far as the way the smoke hits your palate.

Longer just means you get to enjoy it more.