I think of the NCC-1701 -- both TOS and TMP-era configurations -- as a sort of puzzle. It's fun to try to piece together the innards of a beloved sci-fi spacecraft. Part of the fun is that the shows and films leave enough wiggle room for a variety of ideas to be valid.
I suppose that's true, but I think having multiple-reactors (at least two)
is drastically superior to having only one.
Not if the one is bigger and more powerful than the three.
The aircraft carrier Enteprise (CVN-65) as launched had eight
nuclear reactors. At some point those were replaced by four more powerful ones that do the same job.