I mean, Berlin Bank was pretty much a stock Asylum styled map with a buyable max ammo and it was pretty popular.
I don't think that a map from 2010 is relevant to a current discussion about custom content. In 2010, people were amazed when a map was even released that was playable. The extent of custom weapons was modded weaponFile stats. Maybe a custom map texture here and there if the map was
really cool. And if you had ZCT Mod on your map, well then holy shit it's time to download! See what I'm getting at here?
If you released a Berlin Bank today (assuming no one had played it before), it would be one of the most boring releases of 2014 - and this is exactly why it's not a relevant point to make about maps with no custom content being released today in 2014, 4 years later. People rightfully expect more from maps 4 years later because things have greatly advanced over 4 years and help is WAY more readily available than ever before. You pretty much can't even browse a site like this (or ZM, TMG, CustomCoD, etc) without running into some sort of tutorial that would be immensely helpful to a newbie mapper. This topic is a perfect example.
So I think your reasoning is flawed because today custom content is easier to add than ever before. To think that people wouldn't be tired of playing the same maps today that they played in 2010 is simply naive in my opinion. Anyone who doesn't make any attempt at adding more content to their map is simply either lazy or stubborn, because you really can't make an argument that no single piece of custom content (no matter how small) could be added to a map to make it better than it was stock. That's just an arbitrary argument.
To GrantDaddy007 - excellent video. I feel the same way about the Zombie Sumpf map and agree with your points about creativity and custom content. Maps should definitely follow a theme and be consistent, at least in my books.