The real reason why it should be avoided is because it is an incredibly complex part of American history, and it isn't an easy thing to compress into such formats, without seeming neglectful or at least begging for a debate.
For instance, I don't agree with you that Cap would have had a problem with the A-bomb drops. I'm not trying to be a jerk, but I will give my reasoning, then you can explain to me why I'm wrong (please be specific) then hopefully my point will be made as to how difficult it is.
To start off, Captain America is the most moral character in all of comics, so I have to prove that it is the most moral choice possible.
Second, I will subtract elements we learned later, such as the planned dropping of Bubonic plague on the West Coast (completely collected, more than needed) and the plane started by Germany, they finished, that was about to go into production, that could have sunk destroyers killing essential cities.
I'll start with the element you mentioned, people caught in a fiery death.
That's most bombing campaigns in general, and in specific, the Dresden Fire bombings, which were in Feb. 1945, presumably before he was frozen.
It was the same basic concept as Hiroshima and Nagasaki, to inflict so much damage they would surrender to save more potential lives, to much less effect. It was also designed to create spreading fires.
Even that was just a 20th century version of the Union's "Total War" also known as Sherman's March to the Sea. Where Confederate property was burned and destroyed to quicken the war's end.
The real point is, would Cap have had a problem if it was dropped on Nazi Germany, since that was the original plan, many people who appose would say no, it would be different.
You see, it wasn't really about a land war, it was about ending THE war.
Japan had been committing atrocities since the mid-30s that needed to be ended. Most famous was Nan-King (which had actions so disturbing I don't even want to type them). And unlike the Nazis, they didn't hide what they were doing,the West saw it, read about, and Japanese civilians cheered.
Ending the War quickly would also free the abducted Korean Comfort Women (some as young as 14) from their sexual slavery.
The entire populace of Japan was being mobilized into militias (admittedly only for when the Americans came ashore), this included lining up kids (aged 11-14) in the beach head to hold off the American forces, with sticks and broken guns for a chance to wear them out and play on guilt.
Once you DO invade a country, it is no longer military cost, civilian casualties rise astronomically, and would do so even more since the notion of what a civilian was, was about to change between the two countries.
And as for the actual soldiers, the MOST conservative estimates were about a quarter of a million (some say 50 thousand) on each side . EACH side, and most CONSERVATIVE estimates.
That isn't including people getting maimed and disfigured, or the mental toll that comes along with war.
Don't forget the freeing of Japanese, German, Italian, and again Japanese, American citizens from internment camps. Which brings up the fat that POWS would be freed sooner.
Then their is the post was aspects of written a constitution for Japan that was more equitable for the oppressed ethnic and religious minorities, and more fair for women, all of who had a much better deal under the new laws...even if it is still problematic to this day for them in the society at large.
Then there was the fact that Hiroshima was used to threaten Stalin out of his planned invasion of Western Europe (a third World War we probably would have used) and freed up money for the Marshall plan that kept the commies form subversively taking over western Europe (shocking how close France and Italy were). Those two, admittedly stretch whether Steve could have known that.
It was all for the much greater good. YEs, it was horrifying, and terrible, but it was also the end of the most brutal war of the 20th century. And OI believe there is no greater moral stance that doing what is best for the most people in the hardest of times. So Marvel's most Moral man would make the most moral choice..
so there is my argument. I look forward to hearing yours, again, to show how complex it all is.
Hope I wasn't TOO much of a jackass.