PR #26056 is the culprit.

I can solve the icon not contained in box in my RTL patch to come as the error is also present there and does not need a specific rtl override.
I can also solve the position of the add Module icon in the same PR.

The other stuff is a bit more complex.
Text too close to image is in fact due to multiple lines and depends on the window width as the width of the quickicon container changes and not the height...
Centering of the icons themselves is also a bit tricky as we have to differentiate between quickicons icons with a + sign in <li> with quickicon-linkadd class an the others.

@Quy
Reverting #26056 solves all indeed (in LTR) except the centering of the Dashboard Add Module icon.
We can solve this last one with

.com_cpanel .cpanel-add-module .cpanel-add-module-icon {
    position: absolute;
    top: -0.25rem;  //instead of 0
    left: 12rem;  // instead of 0
    right: 0;
    bottom: 0;
}

Revert the PR.

In \libraries\src\Toolbar\Button\PopupButton.php, change fa fa-square to icon-square. The other icons use icon- except for the Batch icon.

Doing that now. Will also correct the Dashboard add module stuff at the same time.

Please test #26757