The use of H2O (especially the automl functions) with R/RStudio or Python (or encapsulated in a KNIME node) would give you more output like
- details about the choosen model
- variable importance
- advanced configuration settings thru code
- you could use hyper parameter grid search for GBM or other model types in code
The good news is: all options do work with KNIME and thanks to the MOJO format you can interchange the results between KNIME, R&Python and BIgData.