Have you actually demonstrated that the higher-level languages you are more familiar with just can not possibly do the job? And keep in mind both RAM and disk are cheap, so "just add more" may work if saving space is your motivation for "granular control".
Whip up a testbed in the higher-level languages you are more familiar with to simulate a load test, and see what sort of performance you get. Zero bells/whistles, just "how much of data that vaguely resembles what I'll be seeing can I shove through the pipe.
If that shows you don't get good enough performance, then try one of the tools that will generate a native binary from the higher-level language, and see if that is good enough.
Often our intuition of what can be done with these systems is off by several orders of magnitude. So make sure you really need it before you go all-native, especially because you're less familiar with all-native. For example, latency over a typical Internet connection means you'll be network-bound no matter what language you write it in, so write it in whatever you're most comfortable with.
Also, if there's particular operations that are really the bottleneck, consider writing the rest of the program in a higher level language, and writing the bottleneck in C or C++. All the high-level languages have some sort of native interface.