There are limits on pardon power. If a politician gives pardons that the public doesn't like, they lose their job. It takes a few years, but finer-grained controls really won't help.

In this case we elected a President who categorically said he's pardon people who engaged in criminal behavior for him. The voters expressed a preference for corruption, and trying to fix that after the fact won't help. A democratic country that wants corruption will have it.