Is it possible to change the look and feel of remote X applications running under Xming?

Threw it together, often with at the last minute appended is frequently used for a project that was done on short notice with little planning. It often but not always implies that the quality suffers as a result.

Who designed this building? Looks like some architect threw it together at the last minute.

When talking about computer software in particular, the term kludge is often used to mean a quick but low-quality solution to a problem. Usually it means a deliberate choice to use a poor solution, something the creator is not proud of but was forced to do by circumstances.

There are lots of bugs in this application! They came short on deadlines and kludged it together.

Just install gtk-chtheme

$ sudo apt-get install gtk-chtheme

and call it in a terminal opened in Xming

$ gtk-chtheme

Also, you can use LXAppearance:

$ sudo apt-get install lxappearance

and call it as

$ lxappearance

(LXAppearance is, technically, part of LXDE, but the configuration file it creates is generic for GTK 2.0)

X applications get their fonts from the X server — Xming in this case. You can copy Windows fonts to your Xming font directory to give Eclipse access to more fonts.

I'd love to see an answer to the other part of your question. Wish I had one.

I am afraid you wont get that really pretty. This is not only a XMing problem, but also a general GTK/Eclipse Theming thing.

Just use the native Windows install and be happy.

It does help to check the Xserver configuration for the font path and server and it might also help to switch your window manager on X11 site (session manager or environment depending on what you use).

Eclipse 4.2 also has some theming problems, it might help to remove the CSS files like described here http://www.eclipse.org/forums/index.php/m/872214/