What matters most in gaming mice for FPS: weight, sensors, and palm-grip comfort

[EleanorGH]

I'm a competitive FPS player looking to upgrade from my basic office mouse, but I'm overwhelmed by the specs and marketing for gaming mice, especially regarding sensor accuracy, polling rates, and the actual benefit of ultra-lightweight designs. I have a palm grip and medium-sized hands, and while I've tried a few models in stores, it's hard to gauge long-term comfort and performance during a quick demo. For serious gamers who have gone through several mice, what factors made the biggest difference in your aim and consistency? How much does weight truly affect your micro-adjustments, and is there a noticeable performance gap between a top-tier sensor and a good mid-range one for someone who isn't a professional?