I agree largely with ncrawford82.
(From what I gathered) For the second point I'd like to add that choosing to giving up his own life was the only way he could redeem himself after making the mistake of giving the heart to Einon in the first place (despite genuinely good intentions). Apparently that is enough to earn his place in the stars, which could be up for debate but it allows for a clean cut ending.
The only other way for him to redeem himself (
provided
Einon could have been legitimately imprisoned
) would have been to perform some other great gesture You might argue that he could have attempted to fix the rift between dragons and humans but to what avail? He does kind of do this by sacrificing himself.

1: Maybe you're right. But it's like when people win the lottery and they don't think they'll have to pay taxes at first. Einon was obviously only thinking of the fact that he pulled an arrow out of his heart and thought, "Sweet deal. Better get the dragon under chains before the slayers make my day miserable."
2: I'm not saying your idea isn't valid and you're probably right about the ending, but think in the long term. Everything that happens to Einon happens to Draco as well. So that means they'd have to feed Einon and keep a close eye on him to make sure that he doesn't deliberately start harming himself just to screw with Draco.
That gives Einon plenty of opportunities to plan an escape, by either killing the guard who brings him food, or manipulating any followers who are still loyal to him.
The Same Page
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