Yeah. The AirPort utility has some major deficiencies for me, but not having any QoS features to limit upload speed really kills me. The Internet connection is 100% unusable for all devices every time one of my devices saturates my upload capacity (YouTube upload, large file placed in Dropbox, iCloud backup, etc).
The time capsule functionality is good if you have a Mac. You can still use it in as an access point (AP) in "bridged" mode behind another router.
Now, I have my 802.11ac AirPort Extreme configured in bridge mode and installed behind an Arris media gateway (MG5000) multi-room DVR system. I turned-off WiFi in the gateway, but it absolutely must do NAT so the smaller "media player" boxes with the TVs can use home networking protocols to talk to the gateway (can't do bridge mode and let my own router have a public IP). Unfortunately, there's no way to configure QoS in the Arris gateway either! My only solution would be double-NAT
Gateway (NAT) --> router with QoS (NAT) --> AirPort Extreme 802.11ac (bridged)
..that would complicate using the Arris WHS mobile app to communicate with the gateway. A device running the mobile app definitely has to be on the same LAN with the gateway for the initial pairing process.