409!!! now you're talking about a non cookie cutter engine, but expensive, oh well. But the old 348's look the same, but still kinda expensive to work on, but cheaper than a hot 6.
Oldsub, the 454 is a good choice for hard work, more cubes more power, and lots of parts out there.
But "cookie cutter" engines are all in the eye of the beholder.Most guys use a 350/350 combo cause it's the easy way out.You can buy everything premade and just drop it in, no engineering skills required, don't even need to shift gears once you're done

It's a bolt on billet crowd in bikes too, just the trend today ,like big new pu trucks.