Load Balancing: Simple Round Robin versus Least Connections?

hey folks, i've been thinking about load balancing strategies lately, specifically for a high-traffic web app we're developing. we're moving beyond a single server and need to distribute incoming requests. my default has always been round robin because it's so easy to implement and understand. but, i'm starting to wonder if least connections might be a better fit, especially if some requests take longer to process than others. what are your go-to strategies when you first set up load balancing for a new service? do you find yourself reaching for round robin or something more sophisticated from the start? what has your experience been with the practical differences in performance and complexity between these two