Not only designer enhancements I guess but my top 3 for today:
1. Embedded Views with the functionality as in Loyal View+ from Sisdam (
http://www.sisdam.com.ar/wmen.nsf/contents/vp_overview)
2. Increase the 64kB limit of computations. At the moment there is no way to use a Dialog List with a selection of more than 64kB of text and the "Use view dialog for choices" has to many limitations(database & view settings, loss of previously selected entries). You'll get an idea looking at Loyal View+.
3. Add the Issummary option to the field properties so we would be able to store more than 32kB in a textfield.