Back to Mopar world, I think that, combo to combo, the barriers to a certain power level are gonna be lower if you're starting bigger. That's why I usually advise going with a stroker. If you can go big block instead of small block then yes do that. It'll make it all the easier to make big power.
Yeah you're generally gonna need heads cam intake and exhaust to get to 550, but particularly with the valvetrain and heads, the requirements are gonna be easier with the bigger engine. With a big block you're looking at something like a set of eddy heads and a decent flat tappet setup. With a sbm you're going to be investing a lot more to get there.