Size is just about ok... its noticeable and not super small. About the quality, it is kinda bad, but that is probably the result of you using the artistic filters (?) in Photoshop and try saving the pic as .png and not .jpg.
I'd say flow is just about ok, but that is linked to the depth and the way the render goes. It kind of works but it's the render's problem. For the depth you could use the blur tool and just slightly blur some spots or blur a lot and lower the layer's opacity. Colors in the render blend but not the render as a whole for this you can use clipping masks (you can google how to make one) and using a soft brush, brush slightly on the render.
Finally, what has been said, focal, the focal would be obviously the soldier but it is not well established. For this is suggest using a radial black & white gradient and set it to overlay and mess with the opacity, it's something I use a lot. As for the lightning, it lacks too, a set one at least, the whole signature is kind of glow-y but there's no set point onto where the lightning originates.
Some tips would be using gradient maps, using colors/brushes on different blending modes (as suggested by Nik/Eat too), adjustment layers such as curves would help in the focal too.
Overall I'd say it's pretty good for a beginner and you should keep trying, nice use of negative space too.