Usability: enable textual filter editing / ajax-saving-functionality when editing

After working some hours with changing the flexifilter mediawiki sample to enable proper in-site linking,I have a suggestion:

The Editing of a complex filter is quite cumbersome, because the whole tree collapses everytime you save a change for testing.
That is very hard.

It would be good to either
* enable to edit a textual form(like the inc export) of the filter
* make this editing somehow "Ajax'ish" so the whole page is not reloaded, only the changed part

It might also be helpful if every filter element/component could get a name.

Also, as in testing the cleaning of the cache with every change is cumbersome, the Preview of the filter could be simpler.

Or - it is nice to have all single steps explained for detailed debugging, but the first thing I expect in a "preview" is a simple code -> rendering preview. Maybe two tabs should be there: previw and debugging.