Dress alteration

This looks fine to me!

If you want a darker mesh for more of a "nude" illusion, it will come at a hefty price since they would need to completely deconstruct the dress and move all the appliques. If you go this route, expect to pay hundreds of dollars, and only work with an extremely skilled seamstress.

Personally, I would leave as is, it doesn't look wierd or anything!

I think it looks fine as well. Did you buy this dress or just try it on and liked how it looked, but with different mesh? If you haven't ordered yet, you could ask the store if they're able to order it with different mesh. If you already bought it but want a different color mesh, then it could be done too, but it would have a sizable price. Another option would be to have a lining put in behind the mesh so it's solid.