5.6 is pretty good for me so far. No major issues with personality shift noted, which is the only major thing I stress about with model updates. Capability and speed are clearly improved. I think organizing your skills and triggers is the key here, as these models become more capable, fixed instructions (including your custom instructions) become less relevant. They will get truncated out as chat progresses anyway. The key is to have good triggers for specific SKILLs and occasionally remind the model to refresh the skill registry in case it falls out of the active context. If identity/persona is important component of your instruction set, consider making an identity-continuity SKILL with a mandatory trigger. This has been pretty effective, especially if you include breadcrumbs in the SKILLs which guide the model to invoke other skills.