Matching AI models to tasks

You manage LLMs-as-a-service at a company that improves third-party software performance.

The tool you're working on analyzes logs, identifies bottlenecks, and supports large-scale code refactoring.

After the fixes, it generates natural language reports for customers.

You can choose only two AI models for this service.

Given this use case, what considerations would you take into account when selecting the models?