What are the best practices people follow in respect to images on larger viewports?
What size browser should we design for? Meaning how do we deal with high resolution monitors and what % of users have large screens?
How can we best deal with the height of hero images, as we really need to decide which screen resolution to go with?
Of course, all of this is while keeping to the 12 column grid philosophy 😉
While above comments make very good technical points, I suggest tailoring your work to particular client, which starts by looking at their current site’s Google Analytics – Reporting / Technology / Browser & OS / Screen Resolution. This way, you will be spending your time and your client’s budget wisely by addressing your client’s specific needs as opposed to implementing general guidelines. We actually had to advise our clients on occasion against doing fully responsive design simply because their non-desktop traffic would not justify the expense.