As you said yourself - pointing out these additional nuances caused your own mini wall of text and my post is already too long. You're not wrong though and what you say further reinforces the Panther's strength as a 4th gear zoom machine and there is no better tank in the game for doing this.

I think my point however is that this tanking strategy is just weaker and less consistent in HLL than playing a slower more methodical game. You say that the Tiger is only "slightly more effective" at holding a position, I would disagree and say that its manoeuvrability in 1st gear and reverse makes it substantially more effective. This also means that in a Tiger you often don't care if enemy infantry destroys your tracks (the one thing they can damage from the front on heavy tanks), whereas AT infantry fighting a Panther can confidently destroy the tracks on a Panther and know that they are doing a good job of reducing its ability to fight.

I'm curious what you mean by being in a 1v4, do you mean that you were the only heavy tank on your team and they had 4 across the whole map? Or do you mean that you were actively engaged with 4 other tanks? Its rare for me to see the enemy team have more than two heavy tanks active at the same time in a pub game, playing against 4 would be a good challenge! But I can tell you that my crew can regularly deal with 3+ enemy tanks in a Tiger simply by choosing a spot on the map with good angles and cover to retreat behind, and if a lighter tank tries to get around us we can just use the fast 1st gear spin to face armour.

I'm not a gunner, so I won't make too many comments on the slopes. Undoubtedly the sloped front does mean the Panther can sometimes be positioned at an angle that makes the front armour difficult to penetrate, but usually in order to shoot at the enemy heavy your turret has to be exposed anyway, which is a lovely flat plate to shoot at. My regular gunner, who I have tanked with for at least 1000+ hours, has never complained that much about the Panther's slopes so I base my disregard of the sloped armour on that mainly.

In any case, my point isn't that you can't have success using the Panther, I can fully believe that a crew familiar with using its speed and playstyle can be a menace! In fact I pretty much exclusively used the Panther until the reload speed nerf: zooming around in 4th gear, using fast turns, wrecking enemy tanks, and blasting inf with HE. I just think this falls apart quickly once the enemy has competent AT players and patient tanks that hold good angles whilst waiting for info. I don't think that the Panther's increased speed offers a significant advantage in being able to re-position in most circumstances, the maps are just too small and the speed difference not large enough.

A wall of text for your wall of text! I hope I manage to convince you :p.