Open battle order:

There was a vivid discussion during the 1900's about open battle order tactics for a reason. It was not yet standard for line troops in battle (just as it wasn't standard at Gettysburg to advance with several metres spacing between every soldier).
The Boer Wars inspired the discussion as much as did the new technologies despite the smokeless powder innovation that made closed order + quick firing rifles at least practical in regard to visibility.
An open battle order existed for skirmishers since warfare began and was institutionalized in Velites, Peltasts and other forms of warriors thousands of years ago.
I wrote "(the version of that period)" for a reason.


Strategy and throwing resources at a problem:

Throwing resources at a problem may lead to some kind of victory, but it's not high art.
Strategy is among others about efficiency: How to do the best with given resources (maximization of effect up to the given goal).
To excel with (relatively) few resources is a high art while to come to a painful conclusion after struggling for years is not.

I can build you a home with a billion dollar, but that doesn't make me a great construction project manager and certainly doesn't help me to become a top 100 construction manager of all time. Keep in mind I might take years for what really good construction managers would achieve in months.

To answer a question: What's wrong with spending much resources for victory?
Wrong is that really great generals would have won in months, barely after the federal budget office would have noticed the war. Moltke the Elder would have advanced for a few hundred miles, encircled and annihilated an enemy field army and would have pursued/hunted for the enemy till its surrender in 1862. He would have done so by coordinating several corps from a line setup an encirclement by offering the corps enough freedom of action while coordinating on the operational level instead of failing to copy Napoleon as did Lee, Grant and others.

In other words (taking high cost for granted and pointing at the ability to stay afloat with relatively few resources):
Does anyone believe that grant would have survived the Seven Years War as Prussian leader as did Frederick the Great?