Mobile experience is lacking
The interface on mobile is crushed to the point of being mostly unusable.
I'm not sure it can be properly improved tbh, because of how table-based this is, properly displaying it as a table on mobile looks like an impossible task to me.
No worries! I wanted to bring it up because even in landscape mode it was difficult. I also didn't have time to look and see if you were using a UI framework that made a "best effort" for mobile browsers. Best you might be able to do is add scrolling for mobile so it renders normal size and users can multi-touch scroll around to the content?
I'm unfamiliar with ant, but is there a way to just display a different view for mobile? If the tables from desktop (which honestly also tend to crowd with larger rosters) won't translate, switch them to tabs on mobile. You'd maintain the character list, but have a single column to display vertically rather than the full table