First, these don't suck. For a first attempt they're not bad and in the grand scope of things, there are much, much worse renderings out there. I've not used DAZ studio but have been using Poser for a really long time so I guess there are some similarities.
Next, your composition is good, the action is well framed and the sequences actually tell the story. You've also posed the figures in ways that show what they're feeling as well as doing, there is a sense of weight and motion not easily achieved. And yes, unless you have some really good collision detection, well rigged meshes and some soft body dynamics, and most times even with all of that, you have to pose the fingers, one knuckle at a time, by hand.
Then, you might experiment a bit with lighting. Try the basic 3 point set up first, key light, back light and fill light, there must be a wiki thing about that. One thing that will help sell the image is cast shadows. Again, I don't know how DAZ is at that, but outside of the render hit, it shouldn't be too difficult.
This is a vary good effort, so don't get discouraged, the amount of work you're putting into this will pay off. A few things to keep in mind, and these are some very easy mistakes to make, watch out for over lighting a scene, it's very easy to put too much. The same for shadows, if there is a way to control the intensity and softness of them, that will help make the scene look more dimensional, like the table will look less like a white oval levitating in space. Your background image could be a bit brighter too, skies and horizons are constant light sources, even when overcast.
One more thing and I see this all the time. Fingers, 3 bones, 2 joints. Unless there is something in the way, if the second knuckle bends half the amount of the first. So if the first knuckle bends 90º, the second bends at 45º. This is true for all the fingers except the thumb. Then, the knuckle joining the finger to the hand is a ball and socket joint where the rest of the fingers are hinged, so even though there are options to twist and rotate the other joints, don't. The last thing to look out for is that DAZ figure hands aren't rigged right, the palms don't flex. Touch your thumb and pinky together and you'll see what I mean. DAZ hands can't do that which will be a constant source of frustration. It's just how they are.
So keep at it!
BB.
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