Logos and pictures could be in the settings file to make the config even easier.

For example, logo is in:

./client/head.html
<img src="/logo/openki.png" alt="Openki logo">
./imports/ui/pages/kiosk/kiosk.html
<img src="/logo/openki.png" class="kiosk-logo kiosk-logo-openki">

I'll have a look at meteor templates (not done much with meteorjs until now) and may do it.

https://www.loginradius.com/engineering/blog/index-in-mongodb/

The cover image for the above blog is of not recommended size, You can upload a new image or update the cover image of the above mention blog to 3:2 ratio and minimum size to 1200px:800px