Also, stone wall tower only costs 230 resources where a outpost with springald upgrade costs 275 resources (100+175), able to attack quicker (no time needed to upgrade). Seems kind of imbalance for me.
Here is I do it in action and the build that I think should be nerfed…
Lol. Yes this strat is a pain. I feel it is also not game play in the spirit of how this was intended to be used. On top of what you showed: the stone wall tower stairs can be used before production of that stone tower has started. Laying the plan and having a villager nearby, in range, to start construction is enough to use the stairs to get up the stone wall. The villager does not even need to make a single construction hit. This greatly enhances the early stages of stone wall pushes.
There is hardly any risk in this; villagers are so safe so quickly