Remember to use the trigger word leechaeyoung. You can use LORA weight 1 and Hires fix with latent bicubic antialiased, 20 steps, 0.4-0.6 denoising strength, and 1.25x upscale, BUT I think hires fix isn't really necessary, for example, the classroom pictures are actually the before hires fix versions. I've used ChilloutMix, Level4, and LOFI.

This is my favorite LORA I've made in terms of likeness. The only issue is that the dataset is pretty biased with closeups of Chaeyoung looking left. She just has a lot of pictures showing off her jawline (understandable). You'll have to weight "looking at viewer, from front, upper body, cowboy shot" accordingly. Also delaying the face composition with "[:(detailed face, perfect eyes, glossy lips:1.2):0.2]" helps too with avoiding close-ups.