I think the culprit in this whole discussion is the expectation that DAWs (Piano Roll) are designed for composition. Somehow in the circles of digital composition, I often see people regarding this as a given. Well, they are not, they are designed primarily to handle audio files, and to "interact" with VSTs. Composition itself, happens trough the preference of the composer, which more often than not, includes experimentation through a midi-controller. This midi-controller is more aptly recorded in DAWs, and so I believe here is where that expectation starts.
If we were to accept that the Piano Roll is the main instrument of composition, becomes easy to delegate the role of notation software to an aftertought, to print the score for live performance. The point I make, and that several posters made here, is that this is not the case, the Piano Roll is a necessity we adhere to, only because we are unable to achieve the same results within our notation packages. And we are unable to achieve this because of a third part of the digital music pipeline: performance.
So, splitting the composition process into three segments, we have: composition, performance, publishing. The problem we face is simply that neither DAW or Notation Software covers the three segments adequately, precisely because they are not designed to do so. Notation Softwares are forcefully locked into the latter segment, with glimpses of the first, without ever touching the second. What is lacking is the acknowledgement that the second segment, "performance", is as crucial for "composition" as the ability to input notes itself, and much more important than "publishing", for certain. And that "composition", at least for me and others here, is more easily achieved through traditional notation than piano rolls.
Summing all up: in digital orchestral composition, there should be no distinction between the first two segments, composition and performance. And honestly, the only way I can see this division being removed is if a quality provider of "performance" (an orchestral library such as VSL) takes the whole of providing "composition" as well. There are two reasons for this: First, the library holds all the minutiae of how the samples work and how to make them sound good without hassle; Second, the big assumption I make that composition and performance must be united, only stands when we think about orchestral composition, which I doubt is the primary market for either DAWs or Notation Softwares, but it certainly is for a provider of orchestral samples.