It's always best to test the geographic limits of whatever "zone" you're redeeming for (including the Northeast Zone and the Special Route zones). The two Special zones out west (Amtrak California-branded services and the Cascades) can be great deals, with $100 end-to-end itineraries pricing out at just 1,000 points. You can also use the zone boundaries to your advantage:
- buy a cheap paid ticket to the edge of a zone & combine with an award ticket (say, Raleigh-Boston = Raleigh-Richmond + Richmond-Boston)
- backtrack: start in zone A, find a connection that takes you through zone B and back to zone A. Two zone travel for the price of one zone.

On the other hand, I haven't found many great "regular" (zone) redemption values. CHI-NOL this winter runs $108, and that's riding one train from end to end. A roomette adds $179. AGR redemption for either is about $0.019 per point, which isn't great.

Something I like about train travel, but which AGR doesn't permit, is the ability to add en-route stopovers.