You're wrong though.
Yeah. 17 has displayed a large amount of attacks. 16 had done nothing prior to his fight with Cell, that lasted for one chapter. He does have cool
specials but his moveset is certainly not defined.
16 landed only
one punch and
one kick and then the special moves (hell flame, a grab and rocket punch) on Cell, in a one chapter fight where half of it was Cell hiding.................
In the anime, since 16 was so lackluster, they expanded the fight and gave him generic flurry fists/kicks and I think eye lasers.
You might prefer it, and that's fair. (I can't tell you what to like)
But that's certainly not more defined.
As I said a fighting game doesn't rely on super/special moves only, you need normals and style.
Those are special moves. Can you describe how 16 punches and kicks ?
Look at those.
They're a bunch of kicks and punches. And yet...
So now let's look at what 17 did. I'm not gonna include Super stuff.
(yes that gif is Super but I can't find the Z version, anyway it's the same ability)
Can be his super, offers defensive ability against other supers and can be used upclose for damage.
He could have a Dodge command forward and backward. (a flip)
With fast recovery to allow a dash or attack right after. With the ability to cancel his homing dash into it.
Counter/parry mechanic, since that would be powerful, that could replace his ki blasts entirely on the special button.
On top of this mechanic, give him a Rekka with low or high finisher, that could be used after a counter like this :
Could be his overhead
I can go on if you want, those are mostly manga based I tried not to pick stuff made up by the anime.
It's not advised to post manga panels too much so I'll just post one in reference to show the anime wasn't inventing that.
Well, if we omit the first butoden and ultimate battle22/shin butoden(same assets), not really.
If 17 wasn't playable, 16 wasn't either.