I’ve got a make-shift damper on now so that should help with the chimney placing hopefully.
I’ve also got an oven door I bought for this, so hopefully that helps in the heat up process.
Would it help if I add refractive mortar to the inside of dome and front/side walls for additional insulation?
Also another possibility is to build a step up on the hearth, essentially another layer of firebrick, so that’d be 2+ inches more elevation and added insulation?