Klaas Bentein recently uploaded a paper to academia.edu that’s worth reading through on aspect in narrative.
Abstract: In this article, I analyze how aspectual choice contributes to the presentation of Herodotus’ narrative. I argue that the choice for the imperfect versus the aorist tense for foregrounded events brings about a ‘perspectival effect’ (de Jong van den Berg 2000): while the aorist conveys an ‘external’ perspective, the imperfect suggests an ‘internal’ perspective of a character witnessing the events. I show that such an internal perspective is particularly often adopted at dramatic moments (e.g. battle-scenes, natural disasters, human suffering), thus supporting the thematics of the story. This ‘inter- personal’ dimension of aspectual choice is framed within a larger aspectual model, which furthermore recognizes an ‘ideational’ and a ‘textual’ dimen-sion. I conclude the article by comparing my own approach to that of Bakker (1997), who under the heading of ‘narrative modes’ came to similar findings with regard to Thucydides.
He examines one function of past perfective or imperfective verbs in mainline narrative: where the writer makes a linguistic choice either to use the aspect to convey his own perspective of the narrative or to use the aspect to convey the perspective of the characters/narrative participants.
This is an excellent piece of research on Greek aspect and has plenty of import for other work. In fact, I’ll be citing it in my current project on aspect and imperatives.