Mechanically, Dikoting became a problem due to the much narrower definitions of damage codes. Dikoting was cool, but it didn't provide a massive bonus in SR2/3. Now though, a +1 to DV is huge. It just doesn't fit as well into the current iteration of the rules, sadly.
That makes sense if there's nothing else comparable, but -- like with the original Dikote -- there is: APDS / AV rounds. My interpretation would simply be that a) dikote adds +1 Impact only to armor with ceramic plates (i.e. you're dikoting the plating), and b) adds the 'Anti-Vehicular' characteristic (-4 AP vs. people, -6 AP vs. vehicles and barriers) to a ceramic or high-temperature metal (steel, titanium) edged melee, thrown, or projectile (as in arrows/bolts) weapon. It cannot be added to any sort of high-speed projectile, such as firearm/gunpowder ammunition or gauss rifle ammunition; get AV rounds if you want that.
That -4/-6 is much more unbalanced than a DV +1 though!
I can see Dikote giving +1 Impact armor, and AP -1 to edged/pointed weapons. That, coupled with the inability to dikote the 'cool' stuff, like mono blades, vibro blades, memory blades, fine blades etc could be balanced enough for it to work.
