Tragic hero or foreshadowed idiot?

"Funny, y'know?  After all the highways, and the trains, and the appointments, and the years, you end up worth more dead than alive" (pg 1603).

Okay, this was the point in the play that I stopped hoping that the first question was lying when it talked about Willy's suicide.  However, I do see quite a few symbols and ironies (and ironic symbols) dwelling within the confines of this quotation - I like to try to use a few big words in every post.

The first symbol that I notice is the mentioning of highways.  What drives on highways?  Cars.  See where I'm going with this Costello?  You see, I was trying to figure out what killed Willy and I tossed around three possible sources for awhile:

1. His work.
2. His pride.
3. His son.

But you see, his son had just told him that he loved him.  Unless the father had always dreaded the day to be loved by his son, I decided that that idea should be thrown out rather immediately.  Now, his pride and his work both have equal bearings of truth in this play for my taste, but I think that Miller threw us a symbol to show us which had greater bearing on the death.  Remember how Willy committed suicide?  Yes, by the same means that "drove" him to his death (pun 100% intended).

The irony in the statement was that Willy really did end up worth more dead than alive- wow, I feel like a... <insert noun of your choice here> for saying something like that.  Not only did he get fired from his job, but he even refused to take Charley's offer on a job.  At least now his family was able to pay off the house.