No 4 years (really two years) won't be enough time to completely change things... BUT it is enough time to get things started. People seem to forget that it took decades for us to reach this point where there is basicly single party control within the halls of Congress and in the halls of most of the federal government's many departments. We're not going to magically solve this overnight no matter who is elected. Its going to take many more election cycles to turn things around and root out the rot. Trump, for all his faults and he has quite a few, gives the breathing room to start that turnaround.
But as always not everyone will be happy. Those with TDS, and there are many, will still have TDS. And like with the Democrats right now, some are in a purity spiral on the center and the right trying to find the perfect candidate, someone other than Trump. Like it or not we fight the battle with the tools we have. And for now that tool is Trump for all his faults. He isn't a dictator and his cabinet picks (some good, some bad) have to be confirmed through the Senate to have the ability to try and wield their department powers and begin the cleanup. It is doubtful the RINO's in the Senate are going to recess and let Trump use recess appointments to seat cabinet picks.