How important is it to take design classes if I plan on starting my own biotech company in a few years?

This is a great question.  Most managers (from my experience) have little to no design experience.  Design, as with any discipline, has guidelines which separate good work from bad, but this field of expertise differentiates itself from other business concerns by ultimately being graded by the particular tastes and interpretations of laymen and/or employees which seek to only serve the short term bottom line.  For example, engineers may see the difficulty in the concept's production as an unnecessary hurdle to the final product, despite the communicative and emotional (consumer's positive perception) properties of a successful design.  The product is often dumbed down to reduce the cost of goods sold which can limit the impact a product has in the market place and underserve the product's value.  This can decrease product awareness and make you less money! I wish more executives understood the value of design and how it relates to sales, engineering, and brand perception/awareness.  Design bridges art and engineering.  To answer your question, I think high level lessons such as:  how design impacts business, what makes for good design, cost effective capabilities in your particular production method, and comprehensive branding (from visual language of your product line to marketing collateral) would give you the foundation to smartly communicate with your design team.  But whether you do pursue formal education or not, value your designer's input and work to gel their vision with your company's mission statement, sales tactics, and the bottom line.