AH, the age old question. Heres my opinion [and of course, just an opinion ]

The small block chevys are common, reliable, cheap [sorry, I don't consider an all aluminium LS1 'cheap', its an exotic] and decent performers. You usually can't go wrong with them.

Small block fords cost more to do, but there are some amazing performers out there that are still plentiful and can help keep a ford rod all ford.

Big blocks on the other hand are heavy and hard to fit into a rod, but I do love the torque! even a fairly stock engine [read reliable] can give 500+ ft-lb, more than enough for a strong launch. These is the ones I like. There is NO substitue for cubic inches.

But still, who can resist a slight smile when they tell people thay have a hemi under the hood or see the puzzled look when people spot the tri carbed offenhauser on top of a flat head. Exotics have a certain appeal that make the added expense worth it.

I don't think there is any 'one' right engine, it depends on what you want out of it.