My pick would have to be the A Whole Nother Story trilogy, in which (spoiler warning) you can only travel back in time. But because time is in a loop of sorts, if you go before the beginning of time, you will be at the end of time. From there you can go back to any time you want to. And time paradoxes cannot be produced. Plus, your memories from the previous timeline exist as well as the memories from the new one.
It’s not quite time travel, but a sort of groundhog’s day situation.
7 1/2 Deaths of Evelyn Hardcastle.
A very interesting and fun mystery. It harkens back to cozy Victorian style mystery stories without just copying them and providing a modern writing quality and sense of humor. And it’s main gimmick is pretty refreshing.