To make TARGET really dirt simple, use the TARGET GUI. It is almost as powerful as using the TARGET Script program, and it create scripts that can be loaded and run from the TARGET script editor if you want to transition.
But I assume you like typing all this into a text file for fast entry like in Foxy. The GUI is not fast entry, like all GUIs. But TARGET Scripting can be just as fast if you start with a template. I use templates where all the controller buttons and axis are pre-filled in, but with 0 (no output). Then I just plug in the button combos to make a script. The .tmh file is the place to list all the key combos using define commands, and the .tmc file is where you assign them to buttons and axes on the controller. My template also has a common set of key combos that I use (for example, zoom in/out in DCS).
TARGET Scripts are still pretty dirt simple, but it looks more complicated because of syntax. It is based on C language. Hence, there is a lot of obscure text. But if you copy the examples from the manual, you'll see that it is just as easy to use.
Beyond that, the stuff you want to do works very similar to Foxy. Just different syntax. You use MapKey() and MapAxis() functions to do most of it, but all the kinds of things that Foxy did are still there, such as shifted (IO) and mode (UMD) as well as all the axis mapping features. Plus, TARGET supports all devices Foxy supported, as well as the new devices. So you could combine your Cougar Throttle with the Warthog Throttle and Joystick in a single profile (and just set the Cougar Joystick off to the side).
The documentation for TARGET is pretty complete. But you do have to read through it and try the examples. Or, use the TARGET GUI where you can program things graphically, but there is a button that will show you the script it is building - hence you can create complex configs in the GUI and see how to do them in the script. The script created from the GUI runs in the TARGET Script editor. The documentation for the TARGET GUI is also very complete. Again, you need to read through it and try the examples.
For a tutorial, you might find the best organized tutorials on Youtube. Beyond that, most of us just spent time trying the examples and learning as we go.
In the end, TARGET is way more powerful than Foxy. It is C. If you want to do any kind of logic in Foxy, you have to use flags, but flags were painful to use for anything other than the most basic logic statements. In TARGET, you can set a variable (a flag) and do if else statements on the flag to determine what output a button will create. I have done scripts where most the script was all custom C code to do stuff that would have been impossible in Foxy. For example, neither Foxy or TARGET supports the ability to map an axis with zones _and_ have those zones issue different keyboard combos depending on the direction the axis is moving. But I was able to write a custom routine to do this. I also added audible feedback to my scripts using calls to external programs. There are several posts in this forum about how to do stuff like that.
Just like you had to learn Foxy, take some time to learn TARGET, and you won't be disappointed. If you have questions, many are already answered on the Internet, or ask here.