A few months ago, when I was excited about Indy (and more excited about 1/6 scale figures in general) I might have bought any number of Indy-related figures, but I don't see that happening now, even if they get around to releasing them.
That's the worst part. Missed opportunity. How much does that cost a company in this business?
Now, like you, many will pass on Indy figures. Many will cancel Belloq when he finally arrives, just as many cancelled Indy to make room for Gen Kenobi. It's very sad.
I'm certain Sideshow had more planned for this line, but the combination of delays and modest interest has clearly finished things off. Like you, I doubted we'd see a lot of 1/6th pieces, but I figured 4-6 most likely. My guesses would have been: Toht, Mola Ram, Henry Sr., Marion, Spalko. I didn't see Belloq coming, but I think that shows that SS was digging into the line and Belloq was just the easiest (read: most profitable per figure) to release quickly. That, or they figured let's give Indy his main villain in Raiders and call it a day. Again, like the Bond line, perhaps they were planning an Indy with villain from each film. Indy-Belloq, Indy-Mola Ram, Indy-Henry (not a villain but a good pairing for that film) and Indy-Spalko. I would have been satisfied with this attempt, and probably bought another 2-3 figures from those groupings.
Whatever SS had planned for, I doubt they'll take it through to production now...not with other companies bailing out. They'd just lose money and have stock in the warehouse for months or years.