Timing gurus. Recommended initial and total timing for a warmed ove 273 commando?

Sounds like you're on the right track. If it likes 19° initial and doesn't kick back against the starter when you crank then that is good. A rule of thumb is total at 32° and all in by 2000rpm. That's just a guideline. Your total is past 32° but as long as it doesn't ping you're ok. Stock reworked distributors may be limited to 32° total until you plug in the vacuum advance and then it can end up around 50° with no problems. The springs control how fast the advance comes in and the weights and pins limit the total. Let's talk about springs. You may benefit by taking the heavy spring out and replacing it with a lighter spring. The advance will come in faster and it might be even peppier yet.....or it may cause ping because it comes in too fast. You just have to try different combinations. Your engine combo sounds killer. We will need a video when you get it all dialed in. tmm