I did some research on Kyrie Irvings Advanced stats...and needless to say...they're terrible.
According to ESPN, Irvings 'Real Plus/Minus' is 29th in the League. Dellavedova is 16th,
Irving has a 'Plus/Minus per 36m' of +5.9. Dellavedova per 36m is +8
His Assists per 36m is 5.2. Dellavedova 6.4
His True Shooting % is 55 same as Dellavedova.
And his defensive rating is the most damning statistic...Ranking 79th of 82 Qualified PGs. Dellavedova Ranks 20th of 82.
The Cavs best "2 man lineups" with a +16.9 Rating - James/Dellavedova & Love/Dellavedova
Summary
If you take pure Volume of shots out of the equation, Dellavedova is better in every way than Irving.
Kyrie Irving gives you absolutely nothing on the offensive end over Dellavedova except volume. Their True Shooting % is the same, however Dellavedova assists at a higher rate. The Cavs Score more efficiently when Dellavedova is on the court....and their defense is better with Dellavedova on the court. In fact...anyone aside from Derrick Rose (81st) and JJ Barea (82nd) plays better defense than Irving.
The Cavs don't need a score-first PG. They need a player who knows his role and plays defense and makes simple but effective passes.
Its clear forom my research that the Cavs do not need Irving and Love because they both only provide offense....yet Irving provides his at an efficiency rate that is no better than a $1.5m per season backup.
Feel free to poke holes in my analysis....but the evidence is clear. Irving is a volume scorer and nothing else.