Dave:
I was just browsing the archives of the pgAdmin-hackers list and thought
I'd chime in with another alternative.
Have you considered Fox: http://www.fox-toolkit.org
I know you said you have not gotten you head around C++
but there is a binding to ruby http://fxruby.sf.net
Ruby is a cross platform language that you can find here:
http://www.ruby-lang.org
and has a binding to postgresql via it's DBI interface.
Some on the ruby list say it is easy for traditional VB hackers
to learn.
my 2 cents,
-- Tom.