For the sake of not derailing this topic any further (hopefully),
Any thoughts about Goku's new idle?

Way better, smooth as hecc to match and

Pretty nice. He looked kinda static before.

Pretty cool!

It might be obvious, but a character shouldn't be meant to kill mainly by throws, his specials are OK, but his forward and back throws should be nerfed and his smash attacks or another move should be buffed instead

I feel like there should be more Dragon Ball super characters in Super Smash Flash 2

You're getting Assist Trophies at best.
Devs said that Luffy was the last anime character they were gonna add.

Is it me or does this new Final Smash feel a little janky and unpolished? Having the whole rush attack take place in the stage itself instead of a different place like Sandbag's and having no sound effects for the transformations (after the initial one) or even the actual attacks feels kind of...low-effort. There's also the way it's initiated, with him just transforming and charging ahead instead of using a trapping animation like the other trapping Final Smashes. Finally, the last attack tends to glitch out on places with low blast ceilings or pits, with Goku being stuck in that last state until it finally goes off the screen or hits a floor.

If you're gonna take the Final Form away, why not just keep his Final Smash a simple spirit bomb instead of a buggy attack rush? Just my two cents.

The Idea is great but it's poorly executed. They tried making it look like Goku's fight with Jiren where he goes various forms and powers up his spirit bomb with SSB.

His final smash is really cool and good looking, the problem is that it feels very rushed, and it's not exclusive to him, it's the same thing that happens to luffy's and black mage's final smashes, those are even more rushed.
They should just add some attacks and/or decrease those final smashes speed to make them last longer and look great.

or just make them into cutscenes

Yeah I have no idea why they didn't just go the Ultimate route like they did for Megaman if they're just going to remove their Final Forms anyway.