the stug is a good dps, but on the attack it isn't ideal. It's still relatively thin skin with the usual casemate weakness.
The panther is significantly more handily in an attack. Its mix of speed and armor means it can take some hit, escape, repair, rinse and repeat.
The king tiger have many balance issue that make it a nightmare. A slightly slower panther with 960 hp shouldn't be impossible for the Allies to deal with.
The current wehr panther have OKAY dps with high penetration and decent mg for dealing with infantry. It's good at winning fight if not necessarily fast.
By comparison the king tiger with its 240 damage cannon and 6 second reload used to wipe squads and tank ridiculously fast. (less so now that scatter was increase)
Id agree making the panther slower with more HP is fine, just pointing out that making the tiger a nondoc is a bad idea. Also I'd say making the OKW panther reload so slow was unnecessary and that probably needs a tweek.
Stugs can be clunky as they require a lot of micro to use effectively but as seen in top level play Stugs can be used effectively in Attack when used properly. Also Command Tank aura makes it much more beefy but thats another issue for another thread.
Issue with KT is that its ridiculously difficult to balance properly. Since its avaliable to every OKW player making it too strong will see what we saw prepatch. KT rushes that are wiping everything or current patch in which its barely used. IMO making the KT doctrinal will allow it to be more powerful as it locks you into a doc.
I agree Panther is much easier to use on attack its also able to quickly reinforce areas that are under attack when compared to a Stug or jp4. It just not worth it right now when compared to massive upside of those two.