I ride in halters (especially rope halters) often and keep super soft hands with them. I’ve never had any issues at all. I would just watch for signs of discomfort from your horse more than anything. She seems like a pony who lets you know if she’s uncomfortable. As for bits, I’d try soft ones… curb bits definitely aren’t usually too comfy for the horse so I’d try a Mullen mouth bit. They’re very gentle compared to a lot of bits out there! There are happy mouth bits that have been good as long as she’s not a bit chewer. Hope this helps! 
