I recommend using multiple locks. What is important is their usability: try to make sure that the lock can be attached to the frame and that it doesn‘t rattle, also needs to leave enough space for lock up your bike to things that are not the typical bike rack, like lamp posts. I still recommend U-Locks but they‘re so bulky and can seldomly be attached securely to the frame without rattling, so I ended up putting it into my panniers all the time. If you know that you will always commute to a bike rack that allows you to use one of the smaller, hand-sized U-locks, go for it. A folding lock is less secure but very flexible for locking up and often comes with a great, hassle-free frame mount. A cafe lock is not so secure either but is super quick to lock up. Having a complicated lock routine for a bike you can’t afford to have stolen makes you hesitant to stop for short errands or exploration trips by foot. So try to look out for quick, fun to use ways to add security barriers for thieves, because you essentially want to make it slow to break through those barriers and that it requires multiple different tools. Also, you can hide an AirTag or dedicated trackers in non-obvious places.