Currently I would simply like to find all files that have not been modified in the last X days but ultimately I would like to be able to make more complex queries against my sub
With Powershell you can do some nice querying on the log messages
$data = [xml] (svn log -r "r1:r2" --xml)
$data.log.logentry | where-object {$_.message -match "regex"}
Or even on the files changed (with some required magic to avoid a well-known powershell issue)
$diff = [xml] (svn diff -r "r1:r2" --xml --summarize | %{$_ -replace "item", "item1"})
$diff.diff.paths.path | where-object {$_.item1 -eq "file"}