Gradine
🏳️⚧️ (she/her) 🇵🇸
As an aside, I realise that initiative is very handy (especially for some classes), but is it really such a major thing overall? I mean, after the first round is over, does it really matter what your initiative count is? Obviously going first in the encounter is great, but after that, it hardly matters, doesn't it? If you disagree, please feel free to correct me. For now, I personally can't see initiative as ever being more than a second-tier priority for a character, given that 4E is generally NOT lethal within the first round of combat.
I will say that, depending on party makeup, having high initiative is easily more important in 4e than in previous editions. Positioning is far more important than it has even been, especially early on the battle. If the monsters go first and the party defender goes last, your squishier comrades are going to take some hits, and you're going to be spending the better part of the first round or two setting up your positioning.
Still, it isn't very vital, and if you're not boosting Dexterity for any power-related reasons (or possibly for feats down the road) than it's not worth boosting just for the Initiative bonus. After all, there are plenty of feats that fit the bill, and I do believe a few of those stack (I could be wrong on this, however.)