I hope you used amsnag.net if your days are somewhat flexible as it is the easiest way to find the best Amtrak rates (you can search multiple days).
Amtrak fares vary wildy and strangely including business class sometimes cheaper than flexible coach (we'll be paying $81 for BC from Cary to Washington, DC vs $129 for flexible coach), roomettes as cheap as coach, bedrooms cheaper than roomettes or withing less than $5. Now the latter two don't happen often but they do happen.
Use amsnag to check if you can get a roomette cheaply for part of your trip just to experience it. Meals in diner are included. You may find you can travel on part of the route in coach, then part in roomette then part in coach for little more than coach the whole way. Roomettes have shower access. Why th little difference? If rooms are not filling, their price is low. Since someone in a room is not occupying a coach seat, if lots of people are going coach (say a school group), he coach seats are high but rooms are available.
I've also seen prices from Atlanta to NYC in a roomette more expensive than Anniston, AL to NYC even though Anniston is on stop further. Why? Apparently since most rooms are taken by people getting on in Atlanta, Amtrak reserves a couple for those getting on before. If the latter are not taken, the price goes down. You may catch a deal between city pairs. It will take some work but it can be done.
In the future use amsnag as your guide. Note that amsnag prices for roomettes do not include the rail portion whereas Amtrak bundles them together but if amsnag shows a low price for a certain day/city pair, Amtrak's price will be equally low, though higher to include the rail portion.
Rooms are private and not charged per person. So you will have a room to yourself unless someone you want to travel with you does so. In the latter case, you pay only one charge for the room and two "low bucket" rail charges.
Check out discounts - seniors, AAA, NARP, Veterans Advantage. Sometimes you save more than it cost to join.
I assume you joined the AGR awards program. If not, private message me before you do and I'll recommend you giving us both a 500 point bonus. Also, you can gain points by shopping online at such places as Home Depot and Wal-mart.