The author of my linked article also really didn't care for branch delay slots, which I am assuming was a carryover from the original pipeline that is long gone from modern designs.

I know that ARM removed many performance-adverse aspects in their 64-bit conversion (conditional execution, direct moves into the program counter), and I wonder how much was done for the 64-bit MIPS and SPARC instruction sets to make them more practical and less of a historical anachronism.