Yes. In fact, for things like your Team page, we always suggest using your images. Ideally they are professional photos, all taken at once against the same background, etc. But we can also use photos from LinkedIn as long as they look professional. If you do not have professional photos or reasonable quality images of the team, then we advise leaving them off. Names and titles will work fine.
In terms of images for page backgrounds, headers, sidebars, etc, we're a bit more picky there. There's usually a theme to the design, so if your images aren't a great fit in subject, style or color, we may suggest you stick with our selections or another alternative. It is not critical that the website uses actual photos of your specific offices, city, or people. Sometimes they are preferable, sometimes not. Look to us for guidance there.
The most important thing about the images we use is that they look professional. We never want overly 'stock' (we all know what that looks like), and we always want to fit the tone of the website and your messaging. We select all of your website images carefully, but if an image doesn't fit your taste for one reason or another, we can make changes to suit your preferences.