How to make one wide tileable, vertical redstone in minecraft

In 1-tileable redstone either avoid dust like a plague or painstakingly engineer the power levels it emits. There are many techniques for transmitting signal in 1-tileable way, and using the best for your job is pretty important.

If you still want the torch cascade, you can exploit the quirk of comparators that they can read container through a block and output its fill level, unless the block is powered to power level 15, then they output 15.

A much neater way is to utilize interleaved slime and honey with pistons (transporting power by up to 12 blocks).

Or you might want to employ pulse-based transmission and simple T flip-flops (just a sticky piston with a redstone block, powered by a short pulse, like from an observer) to convert levels back. One of methods of transporting the signal down like that in 1.16 is using walls and their behavior of forming pillars when something attaches from the side - e.g. a trapdoor opens.

Or you can use observer chains - you can save a lot of resources and speed things up by interleaving observers, solid blocks and blocks that change state in an observable way, like noteblocks or trapdoors.

For horizontal and diagonal transport, rails (powered and activator) are particularly graceful, especially that you can mix them and one kind won't power the other even linked end to end.

Or - as mentioned in the beginning, use dust and specific distance and power level, so that the signal only reaches the destination in the desired slice.

There are other curious and tricky ways of transporting signal in a 1-tileable way, but I think this should get you started.