I feel like we had a separate task for it already, but cannot find it.
Anyway, one immediate issue that comes to mind is that log_id alone is not sufficient and some indication of log type (or source) should be included as well. This is because not all logs are stored in the logging table. The most obvious example is AbuseFilter logs. Other extensions may also have their own logs and want to expose them in CheckUser (e.g. Thanks althought we have not integrated it yet, or MediaWiki-extensions-LoginNotify as discussed in T174492)