In my campaigns we typically don't rely on material components, allowing casters to use any spells as long as they have the right spell slots available. My impression is that using components would be more challenging, since players' spells would be limited by gold, component availability, and carry weight.
Is it significantly more challenging or cumbersome to include this feature? How do others incorporate components?
Best Answer
If you are talking about the material components specifically... Most of the components are fluff, for most casters, most of the time. They choose a component pouch or an arcane focus, and they don't have to worry about the lint, sand, feathers or eye of newt. If they get separated from their focus, the materials needed can be an interesting plot point or puzzle.
Of course, if a material component has a cost, that cost must be paid. The cost of the spell prevents spam casting and may affect casters choices of spells to cast. The cost for Hero's Feast, for instance, makes it so that the party isn't constantly enjoying immunities and advantage on the savings throws. Those provide balance, by making it more painful to cast more power spells (compared to the spell level).
If you are referring to verbal and somatic components as well, I think they serve basic purposes. Somatic components are to force a free hand, and the verbal is a weakness that casters have. It means that keeping a caster prisoner includes gagging them and tying their hands.
Most of the time, it isn't something you think about -- until it is something you have to think about; or you're casting something with a cost.