@RC: Well, the problem with machine empathetic amps is how they could work, since they require you to actually understand all those electrical signals and understand what they do. From what I understand, the mind-control amp does that by using a list of archetypes to find a way to put a copy of the important parts of the mind you are trying to control inside your own brain so that you can understand them and manipulate them directly combined with a bit of whatever soul magic the amp uses. And even then not all aliens can be analysed and controlled.
However, doing something like having an amp that can control machines would probably be a lot harder. Sure, you could use the electric amp to mess with its outputs and inputs but actually understanding what the electricity going through those transistors means is going to be a bit hard (if they even use transistors and not something more advanced), more so because machines (or at least the machines we have today) work quite differently from brains. They're a lot more precise, a lot less fault tolerant, they work with a central clock instead of concurrently (of course, there are experiments for concurrent fault-tolerant neural-like circuitry, like the one IBM released recently, but they're little more than things for academic research right now and even they are quite different from brains). Creating an amp like that would require a way for the amp to make those things understandable for the user, it would require something like putting a modified and simplified copy of its circuitry inside your brain in a form you can understand. More than that, since there are few standards with machines and an enemy can quickly create new ones or change their technology to adapt, the amp would require a way for it to understand what the inputs and outputs do. After all, living things may be complex and diverse but in the end most of them have a simple purpose and goal and a certain number of ways to achieve that goal. Not to mention that space magic might not like machines or might not be able to understand them the same way it seems to be able to do with brains.
The best way to solve that problem for amps would be to put something like an AI (along with a large database to assist it) in there that can sort through the signals, figure out what they mean and pass them to the user in a form they can understand. However that sounds like something that would take a lot of space in one's brain and/or be a lot dangerous. The alternative would be to temporarily give control of your body to Steve so he can do the work for you, but that causes brain damage and is unusable when Steve is not around (because of things like anomalies, for example).
However, the far better solution would be to make this a mix between a computer, a simple AI and a manipulator, a tool that requires both Aux and Uncon. The manipulator could be a combination of electric, magnetic and matter converter, since those seem to be the things one would need to analyze and control most machines. You use the manipulator to sense the machine you are trying to analyse/control and create a copy of it in some sort of memory of the manipulator. Then the computer on board does its best to figure out what the data retrieved mean and what the machine does and tries to translate it into something the user can understand and alter (If it's something made by humans, it should be fairly easy, just create a copy of the material in question (something like a memory dump and a copy of the hard drive that also includes info about the hardware), try to account for any unexpected changes and try to figure out (or at least get some hints about) what it does to make it easier for the user to complete the analysis.) Then all the user has to do is edit that, changing either the software or the hardware to achieve what they want, similar to how the God Machine Kriellya's character built worked, but more mundane (no rewriting the brains of humans to create drones or abominations (although I guess a demoniacally possessed toaster of sorts is possible in the case of an overload)).
Plus, it makes a nice antithesis:
A manipulator cannot be used to mind control someone because the brain is too complex to be understood just by looking at the data it provides, it's much easier to understand it instinctively as an extension of your mind and body. And you need to have some empathy and ability to persuade too (Charisma).
A machine is too different from a brain to be understood instinctively as an extension of its body, not without some time to look at it and figure out what it does with your intelligence, to analyse the code and hardware and put together what it does and how to get it to do what you want. Thus you are required to use a manipulator and have some skill with machines in the first place (Aux).
So people who want to mind control machines go for Uncon, Aux and Intelligence (even though Intelligence is no longer a thing. Maybe general knowledge would help?) while those who want to control living things go for Exotic, Charisma and Will.