Having issues with my first fiddle leaf fig 🪴

This is my first fiddle leaf fig, and I’m struggling to keep her healthy. She started off growing well, but then her lower leaves dropped. After that, I suspect she developed some sunburn. Growth stalled, so I topped her based on advice I received, and she did branch into two new shoots with some healthy-looking leaves.

Now I’m noticing edema, and the newer leaves are coming in smaller than before. Here are the current conditions:
• Watering: Only when the top few inches are dry (I check with a moisture meter and by feel).
• Soil: Standard well-draining houseplant mix.
• Pot: Well-draining container.
• Light: South-facing window (direct sun for part of the day).

I’m trying to figure out if this is a watering issue, soil/nutrient deficiency, or light stress. I really want this plant to thrive, but I feel like I’m missing something important.

What adjustments would you recommend? Should I amend the soil, fertilize, or change the light exposure? Any advice is appreciated!