As you know, the worst thing that can happen is an unintended pc shutdown (e.g. power outage) that prevents a Core shutdown and leads to various kinds of corruption. Having to uninstall and re-start IBD from the genesis block is a major hassle tantamount to having to do a clean OS install after an irrecoverable OS crash.
I don't know how often power outages happen in your area, but you can always add extra layer of protection with UPS devices and surge protectors.
You can even run bitcoin node on your laptop and good battery will serve as a protector, so you could avoid any corruption if power outage is short term, and you could manually shut down later.
You could also think about installing solar panels that could have multiple use cases in your home.
There is no real protection for longer power outages, but you shouldn't run bitcoin nodes if something like this happens often in your area.
Copy/paste or delete old and replace new?
There is no real difference, except that you will probably have to wait a bit longer if you do everything manually.
I don't know what operating system you use, but files are not really deleted when you simply click delete button, unless you use permanent delete option.