A backup drive is worth it if the photographs matter to you. A laptop is optional. The system that works: keep the originals on your cards, copy to a primary external drive, make a second copy on another drive if you can, store the two drives separately, and don't erase any card until the files are home and verified.
The step people skip is the last one. A backup isn't complete until you've opened the copied files and checked them. A drive full of unreadable copies is worse than no backup, because you stop being careful with the cards.
Solid-state drives are compact and have no moving parts, but they still need protecting from moisture and impact like everything else on this trip.
You don't need a laptop just because you own a camera. A casual photographer can bring enough cards and simply leave them unformatted until home. Bring a laptop when it has a tested place in your workflow, not as insurance against a problem you haven't thought through.