Nowadays, Sins Of A Solar Empire doesn't really do too much that its competitors don't also do.
Sins would continue to be my space RTS game of choice for nearly a decade, until the arrival of Stellaris finally made me ask whether it was time to move on. I'd dabbled in other space strategy games before Sins (Galactic Civilizations, Alpha Centauri), but Sins Of A Solar Empire utterly gripped me from its opening cutscene. The sound of each button press, the wonderful space opera soundtrack, and the endlessly invigorating voice line, 'Scouts have found a colonisable planet!' they're all ingrained in the memories of a 13-year-old playing his very first real-time space 4X game, and loving every second of it. Try as I might, I cannot view Sins Of A Solar Empire through anything other than the most rose-tinted glasses.
One a day, every day, perhaps for all time. Have You Played? is an endless stream of game retrospectives.