That’s been our approach for the last several years:
Oct 2018 - Ireland and Northern Ireland, with a rental car. Fairly inexpensive, and places were open at regular hours. Was less busy than on our following Ireland trip, in April/May 2023.
Oct 2019 - Crete, Greece, again with a rental car, which you’d want if you’re going to get around beyond the cities. Cheaper destination, and we were by able to show up in a town and book a room on the spot, without having to prebook well ahead of time. At a couple of places, we were the only people staying there. Elsewhere, it wasn’t completely empty, but not overwhelmed with tourists.
2020 - Covid, no travel
2021 - late Sept/early Oct - Italy. While places like the Cinque Terre were unpleasantly overcrowded, Umbria was not. Rome was also less crowded than we’ve seen at other times.
2022 - late sept/early Oct - Italy again, including Florence, which had plenty of tourists, but fewer than on a prior trip at a different time of year.
2023 - late Sept/early Oct - Denmark/Norway. This was not an inexpensive destination, but we were told repeatedly that the busiest tourism season was over, and it was far less crowded. Unless you want to go in winter for skiing, dogsledding, etc., then fall is when to go. Still pleasant weather, and fewer visitors.
Nov 2024 - we’ve just booked a trip to Vietnam in 2 months. It’s shoulder season, and the tour company is charging just half price, so this is the time to go!