Not about time travel at the end, though.
It has been decades since I've been all that fascinated by time travel as a plot device. But I love it as a daydream. There may have been some interesting TV shows and movies over the years since I stopped watching, but everything I've caught a snippet of seems to fall into one of two categories: 1. Let's go back in time and fix something. Kill Hitler, maybe. Or 2. Let's go back and be knights in armor, stretching the rationale for our being there to the breaking point. Time Tunnel, Star Trek, Doctor Who, whatever. The "future likelihood" devices of Dune and Asimov's Foundation are only category #1 turned inside out.
Or also, because two of my many abortive novels from my early 20's (I usually made it about forty pages in) used time travel as a plot device, I got to see how easy it is to dream up opening variations of this stuff.
As a daydream, those two categories still make for excellent starting points, but they don't really give you much after a few minutes unless you add something in. I also use the idea from T L Sherred's "E For Effort," being able to go back and observe any moment in time, though one can't affect it. One could find out lots of useful things. Solve crimes. Learn where the Indo-Europeans actually came from.
But it is only when you push category #1 that it starts to get interesting. If you fix something in the past, what else gets changed in the present? Arthur C Clarke engaged in the brief speculation of someone who traveled into the prehuman past, killed a butterfly, and ceased to exist. Are we quite sure that preventing even a great evil will work out for good? Can you go back and keep having a whack at a moment in time until you get a present that is really good; or is each reality, once destroyed, forever inaccessible?
Larry Niven has a variation on this that is a fun speculation. If it were possible in some way to get information into the past - you wouldn't have to go there yourself, just get a message through - that would not only affect the present, it would also affect what message the new present sent into the past. It would create a loop, likely instantaneous, where all of reality could get stuck until some equilibrium is reached. Niven speculated that time travel would thus erase itself.
All this by way of prologue. Those of us who get a kick out of imagining the different outplays of time travel, time messaging, past observation have much less trouble imagining how a good and omniscient God can allow evil. It is apparently a major hurdle for many nonbelievers, and even lots of believers have trouble wrapping their minds (or perhaps their hearts) around the idea. But those of us who have played at a limited omnisciences, with at least an attempt at good, don't have much trouble with the concept.
I don't use it as a proof - how can one use a physical impossibility to prove an apparent improbability? But as an imaginative exercise, it's where you want to go. Carry that daydream around in your head for a few years, and the question of the existence of evil will not haunt you so much.