When age circles are shown in "Name" column, they are located on the left side.
When age circles are shown in "Modified" column, they are located on the right side. Personally, I would prefer the left side (or the option to customize it).
The left side will be consistent with "Name" column and also it looks more logical to me. Age circles works as "summary", the actual date works as "details". Normally, you will look summary and then details, not vice versa.