The main fun and rewards structure in Diablo 2 (which I assume you're talking about - that or a clone) is the equipment, which you can't predict before you get, and which drops nearly constantly (with good equipment a bit rarer, but you're always assaulted by limited inventory and having to prioritise whether you need a piece for your own use, to sell, or whether you'll just leave it). The skill trees are there for the planner and optimiser - you can't really make bad decisions by choosing whatever sounds good, since your options at any given level are limited, but you can look ahead, sure - that prevents you from... (read more)
The main fun and rewards structure in Diablo 2 (which I assume you're talking about - that or a clone) is the equipment, which you can't predict before you get, and which drops nearly constantly (with good equipment a bit rarer, but you're always assaulted by limited inventory and having to prioritise whether you need a piece for your own use, to sell, or whether you'll just leave it). The skill trees are there for the planner and optimiser - you can't really make bad decisions by choosing whatever sounds good, since your options at any given level are limited, but you can look ahead, sure - that prevents you from... (read more)