I like the scape! It may seem bare now, but as the plants grow and the fish mature it will dill out nicely I think.
Regarding the JD's... I kept JD's before and I found them incredibly shy & secretive. Almost always hiding. However, once I had a pair and they spawned it was as if a flip was switched and they became vicious killers. Separated the pair and they were shy again.
If you only have a single hiding place the JD may claim it and defend it - if you are concerned about aggression you could add more caves and sight breaks.