Well, yes, this is possible 
The simplest process I can think of for your use case is this :
1. Build a step as a template
2. Select an area around the step
4. With the area selected, instruct a script to reproduce the placement of the blocks in the selection in an incremental pattern, with x, y, and z increments specified, with a limi
An example of such command could be :
/we replicate <count> <x increment> <y increment> <z increment>
However, this can have a serious impact on the game if coded in Lua, as placing a single block will broadcast to all players... then imagine someone selecting an entire house and replicating it 30 times! .. Yes, if a script can allow something, you bet someone will do it.
This feature will be implemented at some point, but not now. But consider that it is already faster and easier with world-edit to build things
you can use the arrow keys in the chat to re-execute older commands. With the -p flag, it's only a matter of replacing the selected area with the arrow keys. 