Logitech G703 is a great lightweight gaming mouse because of its low click latency, up to 25,600 CPI, and three extra programmable buttons for your MMO craze. You are getting instantaneous reactions, and its shape will fit nicely with most hand sizes and grip strengths which won't cause fatigue even after prolonged usage.
The logo and scroll have RGB lighting built-in which is visible in well-lit rooms, and you can even customize it with software.