The stair looks modern to me. The iron balusters would look more Mediterranean not less. The front door, sconces, and other decor fit the theme more than the stair.

I would not do wrought iron, but would eliminate the stepped wall install a railing with cabling for a clean and modern look.

If this was my design dilemma, I would save up and renovate your stairs. Open it all up by getting rid of the drywall and installing a proper railing with balusters in the Mediterranean style you want. Anything less will look like a bandaid fix. This could be a real beautiful feature of your house. The potential is there.

Your architecture seems too modern to be Med. What is the exterior style of the home? A few Med accessories and accoutrements will not make this house Med. You can always buck the architectural style with your décor, but the house may be more marketable in the future if you don't mess with the built-in style notes, especially if the exterior is a good match with them.