RME will maybe answer this to you on their own ..
But here a few information why I think that something like that will/can not come...
RMEs concept of routing is so powerful and flexible, that you would loose the overview too easily by such wires.

Let me give you an overview.

In TM FX you can create individual submixes per output and route audio
- from HW inputs (with near-zero latency)
- from SW playback channels (from PC with RTL)

TM FX works like a patchback "what do you want to hear finally at the HW output".

So you select an HW output in submix mode and then really "SIMPLY" move the faders of top and middle row.
By this you can create "any submix" for "any output".

Those wires would and can not any added overview.
The opposite will be the case.
The wires would only be a redundant presentation of what you see already clearly on the screen
and it would also overlap more and more the GUI which hinders / robs the view to other important status info on screen.

So rather then requesting a "questionable" redesign I would recommend to learn TM FX 1st.
I am pretty sure that you didn't find and use the small knob called "Sub" on the right hand side of the TM FX screen.

By this you can filter out those channels in top and middle screen, that route audio to the selected HW output (aka submix).

And whether you have a wire or simply watch fader positions, whether they are completely down (infinity) or whether they are sending audio to an output ... well ... this should not make a big difference tbh.

Another thing is, that the current very mature design is also optimized for low latency and low CPU consumption.
And this is also good regarding the other product "TotalMix Remote", that might work on smaller tabplett PCs over WLAN, there is anything welcome, which does not create any additional lag or consumes the CPU more than necessary.

Such a request would require a complete redesign for something, that would not improve anything in any way.
Better would be IMHO to become acquainted with TM FX and to learn about the strength and power.

And submix mode can be understood without any big effort.
Its always the same, select an HW output and then create the submix by moving faders of inputs and sw playbacks as you need to create THE perfect submix for active monitors, phones, external HW, ...

TBH, I personally see  no value in this. Why ?

1. you do not have this variety of modules, that need to be connected. In fact you have only inputs from interface and outputs from computer sending audio to the outputs of interface. And you have only one common effect bus and this only for some interfaces with FX chip (not all).
2. In this representation you can only focus on the connections, it leaves no room for displaying the signals or other things or to be able to quickly react on or to something, or e.g. to mute quickly. In TM FX you have already this clever grouping in these 3 Rows AND you see the signals and everything.
3. you need a larger display.
4. you need more cpu / gpu resources.

If you want to see particular routings, then use Sub as I told you.
Then you only see the channels that route audio to an output.
There you have your virtual lines, but only in a different form of 3-row presentation but straight to the point.
It shows what gets routed into a selected output .. then you click to the output of interests and only see the channels that route audio into that output.
You could not get a good presentation if you would like to create smth like a complete graphic and for all outputs.
Guess how this would look for interfaces with up to 390 channels, that would not scale.

This is far better for operations compared to that. Its IMHO only unneeded overhead giving you no additional value and turning a clear design of TM FX into something highly unefficient. Wasted developer resources for no real advantage.

Please don't get me wrong, just my honest / personal view on this and also as RME customer who is glad that TM FX has a clear concept which enables for efficient work, avoiding everything which would make this concept worse for no real reason.

Hi, you need to expand "Layout Presets" and see below it two buttons (ALL | Sub ).

I certainly would welcome this feature.

There are times you don't need to see levels and a view like this helps finding the hard-to-find routing errors.

Seconded! I think a lot of the confusion with TM would go away if there'd be a graphical representation of the signal-flow as suggested.

Thirded