Groovy Grape dependencies can be a nice alternative for adding Maven repository dependencies at runtime (as an example please see my blog article http://rupertanderson.com/blog/r2-soapui-groovy-grape-dependencies/). To enable Grape dependency management it is necessary to add the ivy jar to SoapUI's classpath (needs to go in the /lib folder, rather than the usual /bin/ext/), making it a bit less of a standard bolt-on.
It could be a nice improvement to add Ivy to the standard SoapUI distribution to enable Groovy Grape dependency management in Groovy TestSteps etc out-of-the-box.
I have tested including Ivy 2.4.0 as part of the current 5.2.2 source in GitHub and it appeared to work OK - not that I have everything of course.
If other people think this would be a nice feature, please vote for this request and I'll pick it up and submit the change for approval.
Here you can review submitted feature requests and vote up the ones you like! If you can't find the feature you want - go ahead and suggest your own idea. Ideas with the highest rating can be implemented in the product.