One weakness: stupid constructs
In one respect, I think the early 2000s Justice League got the GL concept right -- fewer constructs, more use of the ring as a laser/energy weapon. Most constructs look utterly silly. I can stand things like ring-generated pincers to pick up objects -- maybe, although I'd prefer the green energy to be a force field for those purposes -- but to have mattresses or springs built out of light is just silly.
The green energy should be a ray with infinitely variable properties -- narrow or wide, force or cutting, attraction or repulsion, light, etc. No need for ridiculous onstructs