You are asking people who love detailed metering whether it is a good idea to get a standalone meter. We are all going to say yes. But honestly, today's cameras are very good at whole-scene metering. There are a few instances, such as the mentioned snowy scene, where they might struggle. But the latitude of most film stocks and the correction available when scanning can offset these very few instances to a great degree.
Maybe if you live in Iceland or the desert, you might get frustrated. More than anything, a standalone meter is a great learning tool. Otherwise, just overexpose a little.