Barrage isn't a skill most players use because they like the skill itself, it's a skill they use because it has the highest numbers.

I do actually agree there. But since this shows that players choose a number though I would like to mention it's a number where any investment feels good on said number because this is a game where the goal is to kill, get loot, get stronger to kill some more, shouldn't this then be the case of giving the skills all similar numbers at the end? So they are free to choose the skill. Unless these all get near similar scaling they will still get left behind.

Also your suggestion of "rather make changes only to the ones people don't like or play often for x reason" is the definition of power creep. Yes, a lot of skills could use improvements.

I do agree and in the initial stages it would be power creep, but I don't believe people won't single out on a single skill and focus on it until all others have that same power level. When you see things like molten strike, it's again one of those things that start out average and scale extremely well with investment. It's powerful but the others aren't scaling as well. So they aren't likely to really be played. It's very rare in this game for a top skill to get nerfed to where it's still great and many people only play it. They just lock on to the next best in terms of damage.