I'm thinking rod bolts and lifters are the weak points.

There are lot's of things that will break if there stock.

Piston can be replaced.
Rods can be replaced.
Crank well I'd say that could take 200+ HP.
Pushrods can be replaced.
Valve springs can be replaced.
Timing chain and gears can be replaced.
Lifters can be replaced.
Oil system well a dry sump can be used.
Valves can be replaced.
Roller rockers can be used.
Aftermarket fuel pump.
The block and head are strong just how there are really.

If you've got the money most parts can be replaced to make the engine bulletproof.

I'm thinking Rocker shaft and pedestal would be the weak point in a high rpm engine.I havent seen aftermarket ones of them.

What we've got is close to the hemi apart from the fact its not crossflow and the valvetrain, but that has shown the be a very bulletproof engine over the years.