Looks good and congrats on getting the vents. I would suggest alot more plants in there. You need to grab up a few mini neo species ''broms'' as that is what they need in order to breed and deposit tads in along with the fact they will also live in the brom axils. Id suggest a few other plant species like peperomias, philodendrons, fittonia, wondering jew or any other tropical small leaved species. The frogs really do need it in order to thrive,.
I would ditch the fake plants/ vines as they do nothing beneficial for the frogs or the micro fauna. Im not sure you will need the heat cable either as most dart frogs thrive at room temperatures anywhere from 60's to upper 70's. and can venture down to the upper 50's at night without many issues.
Vents will also need a nice layer of leaf litter on the bottom as they hide in it and forage for the micro fauna that depends on the rotting leaves as the bulk of its diet.
Also make sure the light on the viv doesnt over heat the viv. Heat will kill a dart frog faster than anything. So will dry conditions so you will need to cover the top of that Exo Terra with a piece of glass in order to keep the humidity in. They need high humidity which can be kept up with daily misting only if you cover the top.

Michael