Concerning safety, you often have trouble communicating with locals, (comparatively) high corruption and an unstable economy. They are steadily improving but are not quite at the same level as Croatia.
Appart from that, they are not part of the EU and normally don't accept euros.
I beg to differ. I was on a road trip in Bosnia once, and I will never go inside a car in that country again. Roads are poor. Speed limits are more like a rough suggestion. The local drivers are absolutely insane: they take over really aggressively, even with traffic coming from the opposite direction. I thought everything was just "ok standard crazy" (I've lived in Greece, Croatia, etc so I had an idea), until our car was taken over in a narrow tunnel, on a right curve - the driver behind us (or the guy on the opposite lane) would've had ZERO chance.
Roads are probably better in Croatia but the drivers are most certainly not.
Unfortunately the main highway from Zagreb towards the coast is regularly subject to traffic jams in the summer, which definitely doesn't help. But overall I'd still say it's a radically safer place to drive than Bosnia, I've seen more insane drivers in 2 days there than in ~2 years of Croatia.