The main idea is to get as much tagfields in the tag-panel as possible and not to waste space.
To achieve this it would be necessary for the user to have the ability to take influence on the width and the position of the tag-fields.
I have some self-defined tag-fields in the tag-panel that in extreme only need space for 1 character (only a little bit more because of the headline) but without the possibility to have real influence on the position and width they cover much more place than necessary. They could easily be positioned together in 1 row and 1 column like the arrangement of year, track and genre in the original layout.
Normally I don't work with Mp3Tag in full screen mode because I often have to drag and drop or have a look at windows from other applications during my work. I have a 27"-Monitor with a resolution of 2560x1440 and have set windows to a scale of 125 %.
With the new layout of the tag-panel I have to stretch the mp3tag-windows to about 2/3 of the screen horizontally to see the whole tag-panel without the need of scrolling. This is only necessary because when I stretch the windows horizontally the tag-fields in the tag-panel get wider and wider, even those that don't draw any beneficial of a greater width.
To see the resolution of the embedded coverart aside the picture I have to scroll or enlarge the mp3tag-window to 2/3 of the window. And I like to have a view of this resolution permanently.
With the new layout came a larger display of the embedded coverart than before. To have a closer look at the cover-art it is surely better to have this larger display than before. On the other side this new size of the coverart makes it necessary for me to have a wider size of the tag-panel vertically to have a complete view of the cover-art. I think in the past I made a suggestion to have the possibility to blow-up the embedded coverart with a mouse-cliock too, like it it possible at the moment with the separate cover-art in the folder. This would bring much more advantage (have a look at the details) for the user than a slightly larger cover-art in the tag-panel.
I understand that the previous layout with the vertical overflowing tag-fields in the last column wasn't an ideal thing. On the other side I got accustomed to it and a positioning of the tag-fields that I needed not so often at the end of the list made the disadvantage of the need to scroll vertically sometimes not so hard because I had the beneficial to see the cover-art and the most used tag-fields permanently.
Every user has special workflows and preferences and every rigid layout will have disadvantages and advantages for someone. So I think only a real flexible layout will overcome these disadvantages.
For my personal workflow the old layout-limitations were much more acceptable than the new one in spite of the circumstance that the old one did only use part of the possible usable space.
My explanations to the need of horizontal scrolling and the necessity to enlarge to 2/3 of the screen to avoid this refer to my tag-panel-layout with 4 rows and a multi-line-lyrics-field.