E-learning environments have shifted from organization- and teacher-centered settings to platforms for individual knowledge acquisition. They are supposed to trigger self-organized learning processes based on adaptable content representations. Individual learners should be able to explore content according to their mental model of the learning process itself, their current domain expertise, and their communication needs when learning. In this paper we revisit the idea of e-learning ontologies in terms of interactive design spaces coupling content with communication, as they can effectively guide developers in the transformation of learning tasks to features for human-computer interaction. We introduce a multi-dimensional, learner-centered approach capturing social and technical issues. The proposed Topic-Map-based representation scheme can be accessed from both, a content-, and an interaction-oriented perspective. In this way, it enables representations for both, individualized arrangement of content and communication, but also for immersive navigation, given a didactically relevant content structure for learning. Using standardized metadata, as given through XTM, the resulting systems are compatible with respect to content and communication.