I agree with the OP for the most part, being in a Ferdinand shows these flaws a lot more then one would think as it has a very slow speed and turning ability, this makes it better most of the time to just find a corner to hide in near base, using the 200m frontal armor as a shield while you pick away at enemy armor.
As for teamwork, I didn't receive a lot of help when i was working my way up the tree, but, now that i am in the Ferdi, many times i hear people say "help the Ferdi!, or, I got your back!". That being said there are still games where i get left with no support and end the game with two med tanks ramming my side and just unloading while i sit unable to move, but it has gotten better as of late. To give an example, a friend and i play a lot on ventrillo together, he is in a vk3001p(i think, its one of the vk series), and he follows me around, always aiming for the tracks of enemy's that get too close to me, making it an easy shot for my fully upgraded Ferdinand, when we do this i don't think we have lost a game yet.
As far as buffs go, alittle buffing would be nice, but at the Ferdinand level, the only thing im biting at the chomp for is the jagdtiger