Many open areas to explore, but alot of back and forth that can get tedious when doing quests because you have to come back for the reward, and most of them only give you a day of in-game time to finish the quest and collect the reward. If you keep your backpack under 50 kg's and get some artifacts that boost your endurance, you can sprint for very long distances which makes it easier to go back and forth.
The back and forth does get tedious at times.
For someone who'd just start the game, I'd recommend installing two small mods regarding what you were saying: the first one allows you to carry more weight (there's actually a bunch of mods that do that, but to keep it somewhat realistic you should choose 100 or 150), that will definitely reduce the back-and-forth thing (you can also change this yourself in the user.ltx file I believe); the second one gets rid of the one-day limit for most quests. I don't remember their names, but using these really doesn't feel like cheating or anything, and not using them will drive you nuts at times.
Maybe I should have just made a STALKER thread in the proper section, I just love this game...