As a main Weaver since PoF release, and after playing a few hours on Catalyst, my main issues were alot like the ones described here
As a catalyst, a melee oriented spec, we lack:
Gap closer, we have 1 (in 20 skills)
Desingage, we have 1 (in 20 skills)
Heal on weapon, we have 1 (in 20 skills)
Combo fields and combo finishers (can't remember number, but small)
The skill 3 is nice and all, but the duration is either bad, or instead of refreshing it every time you switch attune and press 3, it would increase that duration. But still requires 1 or 2 seconds more on base.
Skill 3 Grand Finale is lackluster, not that big damage even in 4 attunement strike. Should be moderate damage, and bonus damage/effect on attunement use. You use Skill 3 on fire, and then grand finale still on fire whitout attune swap, it should add extra burn, same on water for chill, air for vulnerability and earth for earth, so you don't really "need" nor want to rotate all elements.
Also, grand finale in this way would have separated cooldowns
As for traits, a bit together with the weapon and utility, this is a class that has at least 4 traits, SPECIFIC to work with AURAS.
Unless you're playing fire spec, you won't create any aura on hammer. Might be wrong, haven't tested ALL but even if you can, is 1, maybe 2, on what? 2 mins cooldown? Not worth it.
I would rather play offhand focus or dagger for the "free" extra aura that i can trigger when needed.
As mentioned before, most skills are very slow, you get 2, maybe 3 hits before actually doing a strike. Might sound good of paper with the nice damage number, but you can't deal damage when dead.
As for Jade Orb, in my opinion, the ELITE should have the orb permanently. Period. The F5 would be like "overdrive" it. depending on the attunement the overdrive would give the actual bonus with actual decent damage, but on permanent side, would give some minor boons like herald has.
Press F5 to overdrive, press F5 again to stop.
Jade orb should be orbiting (visually) around you, and never actually static. Imagine herald using any utility boons and being stuck on the ground. See how efficient it would be.
This is enough of my rant. I wanted a bow, but i actually enjoyed playing with hammer, but it needs serious tweaks. According to youtube, it can have really nice damage number and stuff, but is lackluster and needs too much "babysitting" to actually work.