Display in 3 columns Videos, Albums, Groups etc.

Hello. I created feature request about "display content in 3 columns instead 2".

But at the moment I suppose it's not difficult to di by myself.

Seems, all I need is to edit layout files. May be /themes/wireframe/videos/default/item.list.php
and replace to

Also – unpublish "Sidebar Module".
I don't need to display "All videos", "My videos", "Features videos", "Filters"...

Everything I need is a "Add video" button and "Categories" list. Seems I can create a Custom HTML module to display it. But Catories will be without count of videos inside. To display count I need to Edit "Sidebar Module" layout and make it horizontal.

Or may be instead of editing lots of layout, I should edit CSS and change Flex 50% to 33%

#es .es-cards--2 .es-cards__item {
-webkit-flex: 0 0 50%;
-ms-flex: 0 0 50%;
flex: 0 0 50%;
padding: 0 8px 16px;
}

Can you please give advise? What the easy way? Nothing critical will happen if I unpublish "Sidebar Module" from "Videos", "Albums", "Groups" section?

Thanks.

P.S: or may be in future I will use full screen width template and display Sidebar + content in 3 columns ?

P.P.S: There is really no option in backend to chose how much columns is? Or may be I can add some custom CSS class to Menu Item (All videos) and there is will no need to edit layout files or CSS file.