You really want the company logo / site design to be on a login page. When a user accesses a site, he knows immediately which site belongs to him by his domain name, his logo and his company name. The design / brand is often something to recognize. When a user enters a new page to connect, it is recommended to have the same attributes / properties so that the user knows that they are still on the same site and that they have not been redirected.
I do not think there are any advantages, in terms of ease of use, to have nothing. You need to confirm that users trust that they are connecting to the site they think they are, which is confirmed by the name of the company, its logo, its branding and its design.
Steve Krug explains this in his user book, "Do not make me think," in which he explains that the ease of use is increased when the user does not think or need to train, in this case, where it is in your site directory. .
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