Basic Gear

Always wear uniforms for the side of the faction you are playing to avoid being team killed by accident.

You do not need to be able to sprint. Maybe a lil for quick get to covers but you need ammo more than you need to be able to sprint.

You do not need a pistol, but by all means keep it if you want.

It is recommended to create multiple types of loadouts for each role.
Example: if you role is AT, you could have a kit for Autorifleman-AT, explosives-At, paratrooper-AT, Underwater-AT, Marksman-AT, Urban-AT, etc

Always wear a uniform that is easily identified as friendly.
5 x First Aid Kits

2 whitesmoke
1 Greensmoke
1 chemlite of faction color

Gun Attachments
Always have a scope. Either in your inventory or on your weapon. That can help you fire at targets up to 300 meters.
Always take a laser sight for night ops so you can identify targets and your location.
Always take a silencer for your weapon. Either in your inventory or on your weapon.
If your a marksman or sniper always take 2 scopes. One for long range and one for 300m or less.
If you can, take ENVG II instead of NVG
These enable you to use thermals. I do not advocate using them all the time.
But if you can not find a shooter then they help see the shooter through bushes and trees or in windows.

KigBag is great.
But if you have the DLC for it I recommend the Viper Harness
Always take a Rangefinder or Laser Designator

Always take a GPS

Always take a compass

Always take a radio
You need this to be able to use ingame comms.