[Daryl]

In my numerous basic motions practice, is it common for people to bend and straighten the right arm without enough "forward"

I hit shots much better focusing on the right elbow finishing opposite my left hip, much more "compression" of the ball

Would this "not enough forward" be one way of running out of right arm?

That's a great discovery moment. It's a very common problem as you suspect. The Right Forearm is brought into Impact On-Plane so your Right Elbow should continue Forward as you've discovered.

When the Elbow quits, it also leads to a Bent Left Wrist, disrupts Hinging and gives control of the Clubface to the Right Hand, destroys the Wedges, no #3 Accumulator Roll, etc.

Though the Clubshaft is in the cup of your Left Hand during Basic Motion, I still think that you should see the Clubface Rolled at the end of the Stroke (Swingers). This should occur by Rolling the Wedges and not simply by Rolling the Left Wrist. So, is your Right Elbow at least Level with your Left Elbow at the End of the Stroke and not below as it was at the Start of your Downstroke? It's only my opinion.