I hope you don't let your egos get in the way of a constructive discussion.

Ubuntu is fine with Transmission at the moment. I think it's crap. Deluge can learn a few things from Transmission though.
When I said that downloading with bittorrent should be as simple as downloading with Firefox, I was referring to the fact that my mom can just start Firefox, and download a file. It Just Works. With current Deluge, my mom would have to go through a very weird wizard which asks her all these impossible questions. It's scary for my mom, so she quickly closes the application and never clicks on a torrent again.
So, I really like the fact that Transmission doesn't ask anything in a wizard. Any port business is transparent to the user: it just picks a random port in the high region, and tries to open it with NAT traversal. Then in the options there are just two regarding ports: which port to use and whether to automatically map the port. The same goes for the download location: it should just point to a sane default like ~/Downloads and not bother the user with it. If they want to change it, they will find the configuration window.
However, there are two settings that cannot have sane defaults, as far as I know: max connections and max upload. Maybe the upload could be tested by uploading a small file, but max connections has to do with the router and how soon it crashes.

So a wizard with just these two options set at low defaults would be a fair minimum nag, wouldn't it?
Regarding the obscure functionality and plugins: isn't it strange that Transmission is simpler, when Deluge is supposed to have a minimal base client and a rich plugin system? On the mailing list they mentioned all the options regarding the notification area. Why not just move that functionality to a plugin? It's not like the notification is such a basic feature of torrent-use. This is just an example though. IMHO anything that requires configuration should probably be a plugin unless it's essential to the process of downloading with bittorrent. Anything that can work without configuration should probably be included. (Things like PeX, UPnP & DHT should work automatically.)
Regarding high CPU, RAM, disk size. I don't know (nor care) personally, but in the mailing list they told me they always reniced Deluge because of the CPU-usage. They saw that Deluge used slightly less RAM than the resource hog Azureus and told me that Deluge needs 13MB disk space while Transmission needs 1MB.
And the reason I think it's important to be default in Ubuntu is that the world uses Ubuntu, and therefore also uses Transmission. I'd hate Deluge to go down in history as that great client that people lost interest in because Ubuntu could handle torrents by default. That probably won't happen. I predict that, as Deluge continues to improve, even the Ubuntu-devs will eventually see it as the great client it already is, and ditch Transmission.