Branched veins are much better for transporting water. The more water that can be transported, the more efficient the plant is at cooling the leaf surface. Plants transpire water through the stomatas as a cooling system. Cooler leaves and cells are more conducive to other plant processes, such as photosynthesis. Third is the root systems.
Monocots have fibrous root systems while dicots have netted root systems.
A hosta root grows from the tip. That is why there are only a few roots in the pot that seem to circle around and around. If they were stretched out, each one would be quite long. An individual root can live for 3-4 years. Breaking or damaging these roots during transplanting will stress the plant until it can grow more roots at the next flush of growth.