In my previous job, a big part in recruiting new employees was to test their business sense. We got a lot of UI and UX designers that wanted to focus on the new and nifty, rather than the true and tested aspects of the web. When faced with questions where they would need to make a choice, the ones that stood out most were those who were able to get over their sense of style and usability, and go for the essence of our job: the user experience.
It seems a lot more obvious than it is: your opinion doesn't matter, the opinion of your client doesn't matter, your boss' opinion doesn't matter, the only thing that matters is the end user. It's our job to make their experience (User Experience) sublime.
Sometimes that means choosing to go with an ugly design, using elements that are not necessarily the most user-friendly, but are the most recognizable.
A funny, albeit anecdotal, thing I noticed over the years was that the UI/UX-designers that came up with a standard blank template as their CV were the ones making the logical decisions, whereas the people behind incredibly creative CV's were too focused on making things pretty and fit their own sense of style.
In my current job it is no different. Despite our focus on mobile interfaces (responsive design and more buzzwords like that) we still want to cater to the masses; we prefer UI-recognition over innovation. We'll leave the innovation to those who can afford to train our users. We will adapt our UI accordingly, a few years down the road.
So, to come back to the original question, and please note this is purely anecdotal:
How much value is there in using “industry standard” design elements?
Depending on your market: a lot of value. In an e-commerce market where the target audience isn't mostly composed of tech-savvy individuals, you will want to follow industry standards, because that simply makes business sense.
On the other hand, if the purpose of your website is to land yourself a job at a design agency where innovation is key, and they cater to an audience that appreciates this, then I would advise against conservative design elements.
Is it ethical to use common design elements to artificially increase authority in this way?
I don't know that this is "artificial" at all, honestly. I would argue that recognizing common design elements shows a level of understanding of the market. The very fact you even contemplate all this shows me that you do have some level of authority, though a better word would be "seniority", on the subject matter.
Ideally, a contrast of old and new might be interesting to see, depending on your intended audience. If your website is a showcase for job-applications, then I, as the guy doing the interview, would be interested in seeing your familiarity with the old and familiar standards, and I'd love to see that you are still capable of innovative thoughts.
One of my goals for the redesign is to add to my perceived authority as part of my chosen industry.
Never hide your knowledge.