So I to got interested in this after seeing your question, after a bit of goggling with out any interesting results I decided to try my self and see if i could figure something out. This is more of a workaround then an actual solution.
I started by creating a test project using quickly:
quickly create ubuntu-application foo
Then i launched eclipse and created a new python project and imported the quickly project folder. Right-cklick on project->import


Then I added the quickly-project path to the eclipse project: Right-click on project->properties
go to PyDev - PYTHONPATH-> add source folder, and select the root map of quickly project
(This is not necessary but it removes those annoying read markings that complains about not finding imports)


So now the only thing left is to be able to launch the project from eclipse. To do that click on the run-menu at the top of eclipse->External tools->External tools configuration
Right-click Program and select "New" Name it something like Run
- For location enter the path to quickly executeble (/usr/bin/quickly)
- For working directory click on "browse workspace" and select the root foolder of the quickly project
- For arguments typ run
- Go to the tab common and under "Display in favorite menu" select External Tools
Create a new one and name it something like design, the only thing to change in this one would be to type "design" instead of "run" under argument.
Now you can Run or launch glade to change design from the dropdown menu I'm trying to show on the last picture.



For the python question I would suggest that use Python3 because Ubuntu is aiming to only include python3 in Ubuntu 12.10 and forward. (https://wiki.ubuntu.com/Python/3)
As for setting up python in eclipse: when you create a new pydev project, you should see an option to select python grammar version and interpreter. If you cant find the right python version under interpreter click on "Click here to configure an interpeter not listed"
In the new window click new and give it a name, then click on browse to /usr/bin and select the python version you like to add for example python3.2mu, then click apply and ok. now you should be able to select that version from the create new project window



Hope this helps you