1. North San Andreas exists but South San Andreas doesn't. Maybe flint county, whetstone and Los Santos can somehow be merged to form a new map, in which hydra's are replaced by 1 tank and 1 hunter helicopter. All securities automatically carry 2 rocket (heat seeking??) launchers that can be used to bring down the hunter militaryhelicopter. Rockets will be available at some location on the map (just like the grenades) or can be obtained by using a certain command (every 3 minutes or so).
+1 for SSA map. Still, it should be done only after the current maps are complete. So maybe in future it would be really cool to play in SSA!
About tanks, hunters, rocket launchers and seasparrows... Probably it's a good idea to place sparrows at SSA instead of hydras and to see if it will be enjoyable. As for me, YoMama is right, other stuff has no place in PTP. Probably it will have in some huge map like "whole San Andreas" where everyone would be able to use it, so we'll have mechanic wars there.
But I am unsure if it can come in handy with PTP gamemode, so for now I will abstain from a vote. And yeah, unfortunately heat seeking doesn't work in SA:MP.
2. A new faction of Secret Service Agents could be introduced, in addition to the existing security agents or as part of the security agents faction. The SSA exists of 2 agents that are invisible on the map, just like the vice president. During normal gameplay, terrorists are highly encouraged to attack a president that has lost all its security. With this new faction, terrorists don't know if the president is still being protected or not, so they will use more precaution and it might make the hunt more exiting. One could also argue that this might also require a new player called the 'Terrorist Leader' (or something) who is also invisible. Question however is: are you willing to implement more players beside the vice president that are also invisible on the map? Maybe the SSA might only be visible for the team of the president (same for the Terrorist Leader and the terror team).
As for me, there's no reason to add additional classes and to complicate the gamemode without the need... Probably securities can be made invisible, but honestly I don't think that it's needed. So
-1 for this one.