Each such case also defines sets of permissible types for explicit and non-explicit conversion functions; each (non-template) conversion function that

• is a non-hidden member of S,
• yields a permissible type, and,
• for the former set, is non-explicit

In this rule, the "set of permissible types for explicit" is first appeared. But, in these [over.match.copy], [over.match.conv], [over.match.ref] subclauses, they first defined the set of permissible types for non-explicit functions. Presumably, according to "is non-explicit", the former set refers to "the set of permissible types for non-explicit functions". I think the order should keep consistent. The sentence should be modified to be that

Each such case also defines sets of permissible types for non-explicit and explicit conversion functions;

To make the meaning of "the former set" be clear and consistent here.

Issue 2:

is also a candidate function. If initializing an object, for any permissible type cv U, any cv2 U, cv2 U&, or cv2 U&& is also a permissible type. If the set of permissible types for explicit conversion functions is empty, any candidates that are explicit are discarded.

Since in these [over.match.copy], [over.match.conv], [over.match.ref] subclauses, we defined the set of permissible types for non-explicit and explicit conversion function, respectively. So, Is that be more clear if we defined as that

is also a candidate function. If initializing an object, for any permissible type cv U, any cv2 U, cv2 U&, or cv2 U&& is also a permissible type for the corresponding kind(non-explicit or explicit) conversion function. If the original set of permissible types for explicit conversion functions is empty, any candidates that are explicit are discarded.