One way you can do that is to bring the business stakeholders into the discussion. This will help uncover implicit assumptions that may be being made about business needs. The business stakeholders can also help determine how the pros/cons of each solution impact the business and which they're more comfortable with. Business stakeholders won't be able to discuss technical merits, but they can discuss business impacts. This is also a great opportunity to build rapport with your business stakeholders because they learn you're not just a cog in the machine cranking out code. They learn the things to think about and see you more as a valued partner rather than a line item than can be cut to reduce expenses.