Well, that's how some people play pen-and-paper D&D. Experience is awarded at the end of an adventure or at certain more quite "key point". But in a computer game that would take something away from the character building aspect that's crucial for a CRPG to work. Imagine only awarding experience once per act in BD... that would mean you would play an entire act with a fixed skill set and at a fixed level. From a roleplaying perspective this might be interesting but probably hard to get right in a computer game. You could of course split up the game into smaller bits than acts.
Another way is have it such that each skills are group under various categories, with each category having their own experience points. (I believe Anarchy Online, or some other MMORPG does it). So we have combat experience, stealth experience, magic experience and etc. As the player uses a particular skill, the experience point in the skill's category increases. So when the player gains a new level, he can add points to skills related to that category.
Another way is have experience points for each skill (like Dungeon Siege). So as the player uses the skill, it improves. Or we can have both system - the typical level up through experience points and improving skill by using it.
Good point. Act I is quite long and you'd probably get about 3 levels by the time you were rewarded. But given how linear it is, you could have check points, say (bulleted points being optional):
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Any thoughts?
I like the ideas too...but I don't think we have to be too picky about the checkpoints. Quests shall give their XP straight away (so the players can know whether it is worth it or not).
Another common take on the idea is to have a level cap. Hence, to make sure the DK for the Act I patrol are always unkillable, we cap the level limit before the patrol to 8. But then again, I don't find this fun.