I hate critiquing sets ups that are looking pretty darn good!
First off, there aren't a lot of small-diameter perches and a lot of the branches you have are pretty slick. My feeling is they prefer perches that are sized from twigs (smaller than a pencil) to about half an inch in diameter. I would put more up high and fill in the open areas.
One of the problems with plastic plants is that they are so thick and dense, the animal can't move through them. I pull a lot of the tufts off to thin the plastic plants out. Rather than let them hang in one big mat of pretty but basically unusable fake greenery, I string the strands out around the cages, using the almost bare plastic vines as branches. I use the tufts I pulled off and attach them to natural branches. If you use natural branches including the very tips where the leaves are, you can push the extra tufts onto the ends so you get a natural branch with fake leaves.
I've found that two out of three of my adult females (quads not veileds) get quite restless for days before laying eggs. One gets extremely restless when she is receptive. My quads are a pretty docile species and normally just sit around looking pretty, but when they get into that restless phase, they will almost leap out onto my arm to get out of the cage as soon as I open the door. Her restlessness might be because she is either receptive, getting ready to lay eggs or the cage is too small.
I have no experience with veileds laying eggs
and I am certainly not suggesting you do what I do. I use a much shallower bin for my quads, but I've also heard that quads lay fairly shallow. I have hiked through a lot of the areas in the south west of Saudi Arabia where veileds come from and they live in a pretty tough arid land. They don't live in a rain forest! (Here's a link to a YouTube video of a veiled in the wild in Yemen.
www.youtube.com/watch?v=LoBLF1FKB9w Have a look at the terrain and you'll get an idea of where they come from. That is not fog--it is dust in the air.) Some places get rain for only a few days a year so I can't believe the ground is going to be at all easy for them to dig in. Maybe they only lay in November when the rains come. I think that in the wild, they probably dig until they run into ground too hard or roots and rocks that stop their progress. I also wonder just how deep a veiled would dig if it had unlimited soft, easy to dig substrate. I think it would be a lot deeper than 12".
Hope I've been a little help to you.