Hi Switchfoot. With the usual disclaimers that early planing, upwind etc depend a lot of technique also I would say that the Quad 76 get going earlier and goes upwind better than both the K74 and K80 unless maybe, maybe if you put some huge fins on the latter two. But the Kodes have a bit higher top speed. Not that it would matter in waves though as the Quad is also an excellent jumper.
If you look for a wide range, I think the Kode 74 is a bit too small. An excellent high wider like Screamer writes, yes. But too small to be an allrounder. So I believe teh relevant comparison is between the K80 and Q76. I would say these two have a similar range, but with an edge to the Q76 in light wind.
Like Screamer writes, it is also hard to say which conditions the two boards prefer. Both will handle pretty much anything. It's even harder to distinguish now with the quad than it was between Kode and EVO since the Quad improves on the EVO in planing, upwind and the "directionalness" of the ride. But the Kode still has much more of that classic straight line feel that you know from your bigger Kode (but with more control due to smaller size and narrower tail). The Quad delivers at least the same amount of fin grip, but not with the sem "definition" as a single fin.
In turns, the Quads are looser and I would say much easier for making the most of on shore wave riding. The Kode 80 can be made to rip it up very, very well too, but requires the sailor to push it more: ride with higher speed, drive it through the turns with more power and precision etc.
In the end, if it is pure B&J, I would still say the Kode 80. But the more wave riding you through into the mix, the more interesting the Quad will be. And there are a lot less compromises in B&J performance on the Quad then it was with the EVO so you will not have to give up a lot.