Oooh...joining this thread late. That's what I get for getting sucked into Ikariam (premium crack cocaine) and
WoW patch 2.4 (new content).
My suggestion to getting unlocks is as follows:
1) Defib
2) Advance Med Hub
3) Frag grenades
4) Enhanced Endurance
5) Stamina Recovery
6) Max Clip
7) Extra Grenade
8) AR-Shotgun *NS Boots
9) Net-Bat Infantry *AR-Shotgun
10) Rockets *Net-bat
11+) Whatever
Play assault since it's the 'easiest' kit to get points with. After you've got your defibs then you're good to go and you've pretty much covered all the important points. The advanced med hub will increase you charge rate, charge bar, and allow you to act as a living med hub when in a vehicle to those around you. After you've got those basics down (keeping yourself and others around you up) then you NEED to go after the personal unlocks. Playing on the
TG server means being mobile and staying mobile so that means the enhanced stamina and stamina recovery are a must. If you have NS you also want to edge in the increased stamina recovery boots for even more staying power which is why I also suggested the increased clip and extra grenade upgrade.
Why is it not important to get class kits right off the bat? Because this late in the game you have plenty of people who have gone through the trouble of unlocking things for you! The best, and fastest way, to upgrade your class kit in game right now is to just walk over to a corpse (friend or foe but I'm hoping you try to revive the friend first) and poach their kit. If you get an assault kit you're probably going to find it already has defibs and rockets on it as well as an advanced AR if they were using one. Congrats! All the trouble of unlocking that crap yourself was done for you. Also the netbat upgrade isn't high priority because if you're squadded up with another assault (and you will be on the
TG server) odds are they have it already which makes yours redundant.
On the HUD info:
Red diamond is 'eyes on' tracking and is displayed when someone has spotted a target. If the eyes stay on the target long enough then the diamond is 'upgraded' to a bar with netbat information (based on what netbat you have in the group). Everyone can gauge health but that information is modified based on class netbat unlocks (assault netbat shows kit, engineer shows vehicle type, recon has a longer duration, and support auto-spots recons using active camo). The red diamond stays with the target for as long as there are eyes observing it because it is 'updated' through sight and not electronic pings.
Grey diamonds are 'sonar pings' and are stationary displays from the Otus drone and support heartbeat scanner. It shows where someone was when the ping went out and does not update until the next ping.