Transmission should support bandwidth throttling as it helps manage multiple applications that are bandwidth hungry. Also it would be nice if transmission starts supporting priorities where I can specify a priority level for each torrent and it schedules torrents based on the priority. This will save us from manually scheduling (pausing+start). One benefit will be that transmission might pick up a torrent of lower priority if all high ones are unavailable and hence something or the other is downloaded.
I would rather like to see a system-wide interface for bandwidth prioritization that can perform QoS / bandwidth prioritization based on port, protocol or application.
This would make so you can lower prioritize applications such as BitTorrent, and raise the priority of SSH, IRC and telnet. This allows your torrents to go at full-speed, then get automatically throttled on-demand to keep other more important network flow (such as SSH, IRC, web browsing) as fast they normally would run.
Although the speed limits is available in Transmission, but we can't really control the throttle. I have cable internet at home with downloads up to 8Mbps, but uploads is only 128kbps.
When I download torrents using Transmission, even by shaping the uploads to 2kbps for example, the real uploads is actually using the whole upload bandwidth. I am assuming this is because it needs to connect to the trackers. You can monitor this from the network monitor in Ubuntu.
I literally cannot browse any website until I pause or exit from Transmission.