Not sure what "additional tools" you're referring to here. At the Node.js end, mg-dbx-napi is invoked directly through the official Node API and at the server end it connects to the official Cache/IRIS API. There're no other components involved.
Bear in mind that a superserver of any sort is only necessary if you configure mg-dbx-napi to connect to IRIS over the network. The best performance is realized by connecting to a local IRIS instance via its API.
That said, the reason why we developed our own superserver is because, as far as I know, the IRIS superserver does not have a public interface. In other words, it only works for InterSystems products. If this situation ever changed, we would of course converge on the superserver embedded in IRIS. This would make our installation process much simpler.
There are 2 connectivity modes to choose from for mg-dbx-napi.
1. API based - in which case you don't need any superserver at all. So, this mode will work "out of the box".
2. TCP based - you do, of course, need a superserver for this. We cannot use the InterSystems superserver listening on port 1972 as that's a proprietary server provided by InterSystems and, as far as I know, there's no public API for third party products to use. If there was, we would use it. But, for now you have to use our superserver - which is not a big deal for most of our users.