Ideation methods and outcomes have been evaluated in a variety of ways. Our study extends existing work through a qualitative analysis of idea characteristics based on the ideation method used. Beginning engineering students completed two short ideation sessions with a single design problem while following Individual Brainstorming and then Design Heuristics methods. We compared the resulting 1756 ideas from 186 students in response to one of two design problems ("Design a device to feed a cat or dog" or "Design a device to build a burrito"). We evaluated the ideas based on key characteristics and emergent patterns determined through thematic qualitative analysis across all ideas. This analysis identified four measures for comparing the two ideation methods: (1) number of different aspects included in each idea; (2) frequency of paradigmatic ideas; (3) variations on a key paradigmatic aspect; and (4) number of unusual aspects generated. The findings showed Individual Brainstorming supported a focus on system-level ideas, produced more typical ideas and added little variation in key design aspects. In contrast, Design Heuristics supported a focus on component-level ideas, unusual ideas, and ideas where a key aspect was a target for increased variation. The results improve our understanding of how differences in ideation methods may influence the characteristics of generated ideas and suggest guidelines for designers in the strategic selection of methods to improve ideation outcomes.