All that being said, I decided to try and translate Captain America into B/X D&D stats ... because ... why not?
Captain America's MSH "Fighting" stat of "Amazing" means he connects 75% of the time when punching (unarmored) fascists.
That translates to a level 6 fighter (who hits an AC 9 on an 8+) with a +2 for Strength 17--Grub sets Cap's Strength at "Excellent," just below human maximum, so that works out nicely.
Hit points come next and are trickier. 140 points of Health in MSH is suitably huge, but then again the average sword stroke in that system does 10 points of injury (unless the wielder has Strength higher than "Good," in which case it can go up to "Excellent 20"). If I figure that Captain America is good for about 14 sword hits before he drops, and I use an average D&D longsword damage of 4.5 hit points, that gives us 63 hit points.
That's really high for a 6th level fighter, but MSH puts the good Captain's Endurance at "Remarkable 30," which again tops out the range for homo sapiens. So assume an 18 Constitution for +3 hit points / level and 63 hit points actually fits within the D&D range, though it does mean having rolled 7s and 8s on every fighter hit die (I'll chalk it up to Super Soldier Serum).
Intelligence stymied me. MSH has him with Reason of "Good 10" ... that's about a 13 in D&D, but the Captain speaks at least 7 different languages. I'll just stick with the 13 for now.
MSH notes that Cap's attacks with his shield are at +2 Column Shift, but since the Universal Table is mostly in 5% increments that's easy to convert ... a +2 gives us the same probability.
What about Armor Class?
Grub sets Captain America's Agility at "Incredible 40," the highest a character can go before becoming super-human ... 18 Dexterity for a -3 there. Chainmail for Cap's armor and a +2 shield of course ... and I present ...
Captain America 6th level Lawful Fighter
INT 13 63 hit points
WIS 15 AC -1
Chainmail, +2 shield
combat (including adjustments from shield and ability scores) :
+4 to hit in melee for 1d6+4 hit points of damage
+5 to hit when throwing shield for 1d6+2 hit points of damage
additional languages: German, Russian, Spanish, French, Italian, Japanese
I'm sure somebody has translated Marvel characters to B/X before--we did that kind of thing commonly back in the day and Dragon Magazine even ran an article converting the then-brand-new Warhammer 40,000 Rogue Trader to D&D stats.
So what do you think?
Surprised that the Cap only rates at 6th level?
Incidentally that's a "Myrmidon" in terms of level title, a bit short of the level 8 "Super hero."
On the other hand, it means that dwarf which you've painstakingly advanced to level 5 really is pretty heroic in terms of her capacity to kick some butt.
It also adds perspective to the notion that dragons and some other critters, with "only" 10 or 11 hit dice, are somehow less than epic in the Moldvay, Cook/Marsh version of D&D.
Your party may "poo-poo" a mature black dragon, but it could be enough to make the mighty Avengers have to pause and roll up their sleeves.