A while ago, we used hilverd/vagrant-ubuntu-oracle-xe to alleviate the testing bottleneck, i.e. too many developers on too few dedicated testing environments. Since then, i am a big Vagrant fan as this really boosted up our testing feedback cycle time.
However, even oracle-xe is anything but a lightweight installation, so minimizing your base box is a good thing to do.
There are quite a few resources on how to optimize virtual boxes for vagrant. I picked up some of these and documented what worked well in this gist mkoertgen/vagrant_export_vbox_vm_basebox.md. Enjoy!