Squid is useful as a forward proxy for a number of reasons, like caching. Squid is often used for outbound proxying when you are anonymizing requests, i.e. you

Squid is useful as a forward proxy for a number of reasons, like caching. Squid is often used for outbound proxying when you are anonymizing requests, i.e. you might have squid bound to multiple network interfaces. If all you need is rate limiting, you can probably skip squid.