Definitely push rod oiling. I would build the motor with B1Mc heads, if I was doing it again. I left 150 hp on the table by staying with the 440-1 heads. My heads are all done at 900 hp.
What ever you do, keep the rotating weight down to a minimum. Spend the money on GOOD pistons, and head porting. I would be asking a lot of questions about still running stainless exhaust valves, going with Ti intakes. Set the Intake valve train up for some serious lift. If the heads flow better all the way to .900 , I would like to try a cam that could use them. That would mean a gross lift in the .950 range. To do that, an oversize cam core and bearings is probably needed. Only you can decide how far you want to go in that department. The higher the lift, the tougher it will be on parts. A tunnelram will make the most power. Dry sump would also help.
Edit; I see you already have 572-13s. They are short on port volume and limited on flow when you start talking all out best hp motors. They make good power to a point, but just can't compete with a bigger, straighter port and intake valve.