Here is my take on the whole "What should we do with Panthers?". I also found the use of Panthers should be used as the Main Battle Tank of an army. It is not super fast, and not super strong, but it is the tank you mass produce to fill all roles, defence and offence. Lynx are used for 2 roles, 1 early game (which, honestly, Lynxs should have damage reduction, but then that would make Plymouth basically useless, so meh) and 2, flanking. Tigers should be used for offence, and for covering a withdrawal. Guard Posts should be used for defence (cheaper and stronger).
Why is Panthers not used for the role they pretty much look fit for, being both defence and offence? Well, honestly, I think it is because of the lack supplies/logistics in Outpost 2. Since it is cheaper and faster to build a new unit, then to repair current units, Panthers don't really have a role to play. If building a tiger costed 10k common per unit, and Outpost 2 had a magical way of sending units that are injured in the front lines back to the garages to get repaired, then people would still use Tigers, but there wouldn't be a billion Tigers on the map. Also, Lynxs can be used for flanking currently, but if you had a chance to snipe a enemy Tiger that was retreating to get repaired, it would be more logical.
Panthers should carry a heavier gun then Lynxs (possible 25% to %50 heavier), and should be better armoured then Lynxs too. Currently, Lynxs are about equal to a Panther, taking a mere 1 or 2 shots more to kill. This make the extra price of operating a Rare mine less worth it, cause the population and amount of resources gathered can go towards mass producing the fast, about equal, Lynx. Lynxs should not have an armour upgrade. Their main use should be flanking, and exploiting holes in the enemies line, not doing this retarded "shoot 1 shot, retreat till reload is done, then shoot again". Maybe even have them have a range penalty or something.
I am just kinda ranting right now, so I will stop.