Yeah, that would really be great.
Just yesterday I wanted to order the new Kindle Oasis because I think the hardware is perfect (good to hold, physical buttons, …) but was told by a coworker just before ordering it can‘t open .epub files.
Edit: Thanks for all the tips about .epub + Kindle. I just found out that there also is an option to install Software like KOReader[1] if one wants to go the Jailbreak route.