I posted on the Travelers' Helpline at Rick Steves' website about the overnight ferry from Stockholm to Tallinn, and I got some helpful responses.  The one comment that stands out for me is this:
... don't shortchange [the] experience in the name of frugality.
That bit of advice is at the core of my own travel philosophy.  I have a friend who has done some really extraordinary traveling, including a year-long trip around the world with his girlfriend (now his wife), and I envy him his experiences, except for the way money limited his choices.  I don't mean choosing budget accommodations or cheap eats; spending more on hotel rooms and meals doesn't correlate with a better travel experience.  They did a lot of couchsurfing on their trip, which I think is a terrific way to save money and get real experiences with local culture.  But here are some excerpts from his blog that actually made me feel sorry for him:
we didn't feel like spending $20 apiece to climb the Empire State Building
In our last post we left it open as to whether we'd head to Jordan and visit Petra or if we'd go to Luxor instead. Well, we decided on Luxor, and it was purely about the money. Going to Petra was just going to cost too much.
Although all those prices are quite reasonable (who knew Egypt would be so cheap?) it's annoying to be over-charged just because we're tourists.
It is beautiful from the outside, but we didn't pay the 200 rupees (nearly $5) each to go in. Why? We didn't feel like it (plus 200 rupees is more than two meals for both of us).
I'm all for saving money, and I understand being on a budget, but I hope I don't make any decisions to skip something I want to do because of the cost (unless I simply can't afford it).  And I really hope I don't get annoyed about what I'm spending.  I fully expect this trip to cost me lots of money, and I know that the part of the world where I'm going is very expensive, so I'm just going to let it go and spend what I have to to do what I want.  It'll cost what it costs.

I'm going to try to strike a middle ground in reporting the costs of things.  I am tracking my expenses, and I'll share some stuff about what I'm spending on this trip, but I want to write about the experiences I have planning and going, so I'll talk about money only as it relates to my experiences.

So the upshot is I have decided to spring for a private cabin on the ferry and the smorgasbord dinner.