Improving any process is always a good thing, no ethical issues here.
It's just that capitalism society the problem. The money saved from your process is a private benefit. The lay offs, would be no problem in a sane economy, where you leave a job and theres plenty of other jobs availbable. But nowadays in western contries there's nothing to require such a big quantity of unenployed labour. The result is high unenployment and high rate of low-payed employement, and the risk of anyone being fired to be recruited cheaper (2 of my coleagues where replaced by a cheaper guy without a clue. I'm pissed about that, they got fired because we halved the unavailability of our systems? should I teach this new guy in IT? that's not my job... another ethical issue... Will I be replaced too if he learns enough?). Well, back to the point, our current economic system doesn't have a clue of what to do to change this downhill path, and just hope the economic forces and market rules, will solve the problem. It won't, as if we go global, there's no achievable balance of job offers and labour demand, or at least not in this lifetime.. What we are getting is just an stronger bias to a society with richer and poorer citizens sacrificing mid-class in the process. Both concentration of wealth/power in fewer hands both in western economies and globaly, that are not shown in any corporate balance.
As an engineer I improve things every day (little ones at least) and theese are one of the few things I appreciate about my job... Now I don't know if its even good for me in the long run. Shit.