Enjoy the process. Half the fun for me is planning the build. Just during planning make sure you play chess not checkers. Don't just think about the next mod, but where that mod will take you, what is next, and what is the big picture for the end goal as well as leaving room in case your end power goal increases.
I wouldn't mill the heads and if you do ever have the heads off I recommend going to ARP head studs and LS9 gaskets while you are at it. ARP head studs and LS9 gaskets have been used up to 1200 rwhp with good success.
Regardless of whether you go LSA or procharger you need to decide now what fuel you will run and plan the fuel system to handle more than your long term goals. Do it once now and be done with it. Also keep in mind with E85 you can run 10.5 to 11 compression safely with boost easily while with pump gas or even pump plus meth the tuning window is very narrow with compression in that range.
Here is a video of highlights of my current build: