design on popular browsers
Web browsers are improving today, designs are getting more impressive and clients are expecting to see pixel perfect web-development within the most popular browsers. I say you get what you pay for. Focus less on whether IE is two pixels different, and more on the user experience. Not many users have multiple browsers and critique your site by comparison... unless they are a web-developer!
websites with standards
The idea of creating a formative web did not just fall out of the sky. The fact that many websites today require doctoring i.e. the deisgned shell looks good whilst under the hood the code tells a different story and is badly starved of standardised semantic markup and possible functional logic. I would spend the time and money to follow the provided guidelines and do your website the justice it deserves. technology changes fast which could leave your website requiring major surgery.
websites for the majority
Users of the internet are vast and varied. Do you know your market as well as your visitors? Though technical, it is possible to reach out to a wider audience by making your website accessible to as many vistors as possible. Website accessibility is not new to the internet, just mis-understood. Everyone deserveres the right to view your website, make it happen and spread the love, after all its not called the World Wide Web for nothing.
front-end users experience
Its not all about endless clicking or swiping. Each user journey can be tailored not only to benefit your business, it can also aid the user. If the user feels comfortable navigating your site (strategically created web application - buzz word for website) without waiting for large scale images and heavy use of plugins to load, my guess is they will be back.
Mobile devices, smart phones, tablets and laptops come in all shapes and resolutions. Each device having its preferred browser which requires work to make your website perform to its potentional. Having a responsive website usually outlines a large scale development and various technologies? No! What you require is a framework that will do 90% of the work for you. No matter what the size of the organisation this could be beneficial and save you time.