I can see where both sides are coming from.... from what I've read in the threads, may I put this forward?
It seems that a number of people are asking for a Query by Example (QBE) type search, especially those who may be migrating from other software.
In PM6+, there is now Search, Filter and Browse. The one point being made is that the end result is that one is, by selections, arriving at the set pf images you want. The implementation is whether you start with all the images selected (Filter) or none of the images selected (Browse).
That could be the first question on a QBE panel - start with ALL the images selected or NONE of the images selected. Then searchable field names with combinations of AND/OR and search strings (which constitute the EXISTS) or NULL (nothing entered), the result of which will build the SQL string.
Just the beginnings of an idea of something that may make it easier and still provide the functionality that is there now, just another way of looking at it.
-- Ken