Avengers 4: Why Captain America NEEDS To Be Sent Back To The '40s
1. The Howling Commandoes (And Other Movies)
While Captain America being frozen was a necessary part of bringing him into the modern MCU, it, unfortunately, robbed us of one of the most enjoyable parts of The First Avengers - the period-set stories around Cap's exploits with the Howling Commandoes. Sure, we got to see a montage of him kicking Nazi/HYDRA tail, but there are far more possibilities out there for period-set Cap movies. Just imagine how great they could be.
And then of course, leaving Cap alive could mean more modern set Cap movies too - assuming he'd be "rescued" from the past as he was in the comics. While that might sound like robbing him of his happy ending, Marvel Studios will be more than aware that they have to answer to Disney and the shareholders, and cutting Cap out entirely is surrendering a big chunk of potential box office money.
Sooner or later, the studio will reboot or revive and the only way to do that (even with a new actor cast as Steve Rogers) is to not kill him off and to leave open the possibility of bringing him back into play. Given that we know time travel will be possible after Avengers 4, "stranding" him in the past for now would make a lot of sense.
It's just whether they're brave enough to do it...