I think that "Well, it was good" is really a very mixed-message comment, I'm sorry. The "well" at the beginning implies a tone of voice that's just really, um, unimpressed to say the least. Have you tried finding a different standard that isn't quite so dry? "This was good, I enjoyed it," would be an excellent comment to me, and mean the same thing (I hope), without that sense that what you're really saying is, "Well, it was good, but so what?"
As for the rest, as someone who reads about 1/4 of my actual flist because of porn-locking issues, I'm definitely one of those who filters for boredom rather than lack of commentary -- and on the other side of the coin, someone with whom I have a lot of dialog isn't necessarily someone I'm going to go read, if their journal is boring. But that's a matter of style -- some people want a dialog with all of their friends, and that's their prerogative. For everyone who reads like me, there's a million people that read in a dozen filters, or one big swath, or once a month, or not at all. I just try not to be offended when my commenting or writing style doesn't meet up to whatever that other person's standards are for a good experience -- and sometimes I even succeed. ;)