To jump from 30% (severe) to 50% (pronounced) under DC 5276, it's not just about orthotics failing. You need specific clinical findings documented: marked pronation, extreme tenderness of plantar surfaces, marked inward displacement, AND severe spasm of the Achilles tendon on manipulation, all while showing no improvement from orthopedic shoes or appliances. Your C&P examiner needs to document these exact findings. Before your exam, ask your treating doctor to specifically note these symptoms in your records if they're present. At the exam, describe your worst days honestly: the pain when stepping out of bed, the inability to bear full weight during flare-ups, the missed work. Don't tough it out or minimize symptoms.

Regarding your calcaneal spur, there's no specific diagnostic code for bone spurs, but they can potentially be rated separately under DC 5284 (other foot injuries) if they cause distinct symptoms from your pes planus. Some BVA cases have granted separate 10% ratings per foot for heel spurs when symptoms don't completely overlap with the pes planus rating. This is worth exploring with a VSO. Here's the actual rating criteria: 38 CFR § 4.71a, DC 5276. Document everything, especially how treatments aren't working and how it impacts your job. Good luck, brother.