Maybe a fire box heat baffle or 2 tuning plates might be a nice addition. Other than that it looks like it will fix up well. Nice find!
Only other suggestion is if your using that grill brush to clean it up its not going to do the best of jobs. That rust underneath is not serious, but your gonna want to go rent an 4.5" angle grinder for a day (if you don't have one) with a wire-brush attachment (you might have to purchase that along with safety glasses, a couple dust masks and a pair of work gloves) and give it a little elbow grease and you'll have a perfect surface to re-paint. You will not want to paint over any rust at all, you want to take it ALL
If your willing to do that, she'll be as good as new.
Good luck with the project... Show us some shots when its all fixed up!