Of course it was constitutional for the senate to delay voting on a nomination to the SC. The constitution says the president shall appoint and the senate confirm, and the details of how confirmation battles occur, their timing etc, is all left to the senate. That is using the rules to your benefit, not bending or breaking them. There is a difference.
The pardon power is however absolute, and left entirely to the president, there are no constitutional qualifiers there. People always hate some Presidential pardons, and it is of course open to abuse, perfectly constitutional, anticipated by the Federalist Papers, abuse. Don't like it? Pass an amendment (or the modern lib version, persuade Anthony Kennedy that it would be cooler).
OK, we agree, Moore is not a constitutionalist (PS- he's an exception, Originalism is the dominant conservative approach).
Libs never can get over that the Constitution is a specific rule book, not an open document that simply says whatever is BAD is unconstitutional and whatever is GOOD is constitutional. Was prohibition of alcohol good? Opinions vary. Was it constitutional? It wasn't, then it was constitutionally mandated, then it was unconstitutional again, because words got added to and then deleted from the rule book.