In terms of regularity and uniform structure:

• The template element has 4 lines but it does not repeat anything else within these.

In terms of differences between versions:

None. There are no changes from version to version.

In terms of irregularities:

The second version starts with an extra set of curly braces around </script>. In modern programming, this is unnecessary because most environments will handle opening and closing tags correctly when they're in close proximity without them being explicitly there.

This can be simplified:

or

It's also worth mentioning that in JavaScript alone, we should only have the opening tag for every single block level element. Therefore, removing all the <style scoped> and simply having one at the end (if needed) would improve code readability.

Regarding potential issues, there are no obvious ones since everything looks correct on the face of it. This includes using proper indentation and whitespace which is generally important across development teams.

Optimization Suggestions:

Since nothing seems particularly problematic here aside from the extraneous closing tag, no optimizations are really necessary. If you want to optimize your code based upon common practices, then consider consolidating or minimizing unnecessary elements like CSS comments, adding a semicolon after statements where appropriate, etc. However, as per current standards, such minor touches likely represent improvements rather than actual optimization opportunities due to consistent coding best practices.

Let me know if I misunderstood anything! Otherwise, feel free to ask again in case of additional points needing clarification.