It's weak point is the fact it's armor outside the frontal is weak, if he is charging through your lines to get at your tanks throw some AT grenades to snare him, then hit him with AT guns and your Tank Destroyers.
If your opponent has 2-3 Obers just laugh in his face as that Panther will probably be his only AT, so when it dies because he overreached like an idiot he will be SOL and your mediums can eat his Obers. Seriously 3 Obers is insanely excessive.
Okey, I don't know how you are playing but chasing any tanks when you see AT guns and infantry in front of you is not something any decent player would do.
Weak point = rear armor? Really? You can say this about all tanks.
By they way 110 rear armor while Wolverine and Jackson have 120/130 front armor

Please, don't use such stupid arguments.
So how you want to shoot with AT gun if Obers will kill front-man all the time?
And 3 Obers is not something weird. Most of the time you can afford 2 squads at the moment your T4 is ready. OKW is floating with MP.