First off, major kudos to the gang who put together the "radio" adaptation of "Indiana Jones and the Gold Goddess". The effort really shows and it was quite enjoyable. I'll break my quick feedback into three parts. I apologize for being lousy with names, and I'll try and keep any criticism constructive.
The Good
Sallah was voiced (and sung!) very well. Accent, intonation, emotion, all came through very well. That said, though, Marcus was dead on; the only criticism was that the script only called for absentminded mumbling and distracted banter, rather than the warm fatherly concern for Indy he has in the movies. Still, very close to perfection.
Speaking of perfection, though: Marion! Seriously, I early on wondered if you'd gotten Karen Allen to lend her voice to the production. Perfect voice, perfect delivery, and range of emotion.
The musical choices were a great selection from Williams and McNeely (and any others I missed...), and it was well edited to emphasize the story and the action.
The Meh
The sound effects were a mixed bag. I wanted to hear an engine roar to life and the gunshots didn't quite fit. Others were quite good.
The overall audio mixing quality also varied with the music sometimes distracting from the dialogue. The "old timey" radio effect could have been slightly muted, and perhaps used only on the narration and the intro/outro but reduced during the story itself.
The story had the standard Indy story structure (we join an adventure in progress, there's a dramatic escape, back home to the States, meet up with familiar characters, then the real adventure starts...), so a good choice for an adaptation. I wasn't a huge fan of this story in the comics - it has the one-two punch of first turning the Hovitos into real sympathetic people that Indy was stealing from, then turning them into stereotypical comic book villains. So... well, meh.
The Ugly
The delivery by Indy's voice artist only ranged from "smug, self-satisfied Indy" to "quiet, curious Indy". I would expect this in one of the Indy games where Indy is talking to himself to help the player understand what's happening or is speaking the player's text in a SCUMM game, but in the radio drama, with so much action and emoting by others, the flat monotone was actively distracting for me. Harrison Ford can emote! Indy shouts, gasps, and gets excited about things plenty of times in the movies. The voice artist had Ford's tone right, but just needed to get excited.
My other big objection was with the script, most specifically the choice to use such a large amount of narration. One piece of advice oft given to aspiring writers is "show, don't tell". That's obviously much harder for a radio drama, but IMHO should be done with liberal use of sound effects and reactions by characters with narration kept to an absolute minimum.
Additionally, the narrator also suffered from monotone delivery. If Indy and Sallah are racing across rooftops I want to hear Indy out of breath and barking out directions, AND I want the narrator - if narration is necessary - to keep me on the edge of my seat.
(Admittedly, when I listen to the IndyCast at 2x speed on my iPod, I still think Ed is speaking a bit too slowly... sorry, Ed!)
It's a fine balance; comic book characters - especially of that era - often talk to themselves incessantly to convey their motivations, and I think that approach is over-used. However, in this story the characters are rarely alone and exposition can occur in dialogue or reactions. I guess my guidance for narration would be: try every alternative first, and only fall back on narration as the last possible choice. The "record" adaptation of Temple of Doom hits the mark, IMHO. The narrator steps into set the scene where necessary, and does so with a tense, excited tone. (Contrast with the RA "record" which has no narration and requires the listener to know the movie well, or the LC "record" where there is far too much narration since so much of LC is visual!)
I realize this is a challenge when dealing with limited budget and time; it may simply not be possible to find the foley for every sound effect called for, and narration may be necessary to fill in the gap. But still, I thought 2/3 of the narration could have been removed with no impact to the story.
...
In summary - a fine effort by a talented crew, with some absolutely brilliant casting, a few rough spots and room for improvement, but very enjoyable. Keep 'em coming!