I’m a bit stuck on this one because it just looks too flat and bland. I was aiming for 80% here, which I see as reached, but now I don’t manage to get it above it.
My concrete feelings: the glass looks wrong, the wine looks it’s like from the 90ies and there’s something seriously off with the table. Please ignore the dark green tarp, that has to be reworked. But is the rest of the balcony OK?..
Everything is using PBR textures (except the tarp, that one is procedural).
Rendered with LuxCore as I couldn’t get rid of the edge darkening of the glass in cycles, even with multiscatter-GGX.
Framing is very akward, the way you cut off the glass both on top and bottom. If you must cut it off, leave the top intact and give it some head space… look up rule of thirds as well if you don’t know about framing conventions.
Agree about the lighting, seems off. Delete all your lights, start from scratch. Try to create a stronger key light from either side to give it more depth.
As you mention yourself something off about the table, if anything at all I would say the wood grain structure on the right hand side is kinda big and distracting but I think reframing and relighting will have a bigger impact. Otherwise nice terrace, I don’t mind the tarp at all
I’d frankly suggest that, “in contriving two or three ‘straight-line intersections’ between the wineglass and its surroundings,” you’d probably already sunk your poor ship. Because, no matter what you do now, I just think that the whole thing’s doomed to "look … contrived." “Artificial.”
To make the water not so flat, go into edit mode, face select and select the face that seems too flat the subdivide it then go into sculpt mode and fix it that way, or you can use blender fluid system to make realtime water.
