Does your G502 feel heavy even without any weights? Try placing 2 as shown. It moves the center of gravity, and makes it feel lighter. : r/G502MasterRace
The Logitech G502 Proteus Spectrum Gaming Mouse Review
Best Buy: Logitech G502 Proteus Spectrum Wired Optical 11-Button Scrolling Gaming Mouse with RGB Lighting Black 910-004615