So what kind of system would you like to see implemented in Diablo 3 for upgrading your weapons?"I think it's important not to mistake the word used for a system (in this case rune) for what the systems are actually accomplishing.
In Diablo II runes were used to augment weapons and essentially add more stats to them, runes in certain combinations would create runewords which were in essence more powerful than the sum of each individual rune. But remove the word rune, and you're looking at a system that simply upgrades items.
Similarly, runes in Diablo III, take away the word rune and we're looking at a system where skills and abilities can be altered to behave differently, simply increased in effectiveness, or some combination thereof.
Essentially what your question comes down to then is, where is the system in Diablo III that allows us to make base weapons more powerful? And that's a question that will have to be answered at a later time. ;)"