With over 9 years of game development experience, I am confident in my ability to execute your needs and transform your racing game into a thrilling multiplayer experience. My expertise with the Unreal Engine and proficiency in C++ programming will ensure seamless integration of a robust matchmaking system that pairs players based on varied skill levels - providing a competitive and exhilarating gameplay that retains the charm of your existing version. Moreover, my comprehensive understanding of cross-platform compatibility, particularly with Steam, guarantees no hiccups in the functionality and connectivity of your game across multiple platforms.
But on a serious note, irrespective of my light-heartedness, my commitment to 100% client satisfaction stands strong. For you, this translates to clean code, compatibility assurance across browsers with excellent customer support. Additionally, proficiency in server-side programming languages such as PHP and Node.js ensures a solid backend boosting the reliability and efficiency of your multiplayer racing game.
Given a chance, I will ensure that not only these required functionalities are met with utmost quality within the given time frame but also provide equitable post-launch support thus guaranteeing both project success and client satisfaction.