I vote stick with the factory paint, and touch up if needed. Keep everything cheap and simple. i have an 88 Centurion I am riding...and I weigh 230lbs. It has all stock components, I just cleaned it up and hit the road. Replace those tires, do routine maintenance and leave it alone. if you don't like it then i know you could make at least $100 from the sale in my area...which isn't bike friendly or bike oriented much(houston).

My frame has similarly skinny rear triangle tubing...