I am using a Keelback so I can use a fighter to avoid main ship destruction and my combat rank is expert.
Are you serious?
That is the worst idea I've ever heard from a Rook.
Fighters are not durable.
Once they get focused, they will go pop. They need their target to be focused on something bigger and more durable. Fighters are meant to be class cannons and buzzards. Their job is to screen and clean their mothership from opponents who try to gang up on their mothership and drive them out of the mothership's blindspots into their weapon arcs.
So this defeats your concept because you're trying to keep your ship out of danger. You need your ship to act as bait and keep their attention off you if you don't want to go pop. These weapons are designed to carve through much bigger and more durable ships. Hitting a fighter is like swatting a bug.
Your best bet at survival is your agility. Which means once you get targeted then you have to stop fighting and start dodging. Focus on staying alive and not getting hit. However this kills your TTK immensely which is where your mothership you're trying to protect comes into play to burn through whatever is attacking you and ether kill or peel them.
The other problem where I have to start laughing at you is your thinking that you can just play a fighter solo in a CZ. That's not going to work.
Your mothership can auto pilot and WILL follow you around by default. You can tell it to stay put but then once your fight flies out of radio control range it will self destruct.
The auto computer can fight back but it has a permanent rating of "Mostly Harmless". As I'm sure you're well aware. Mostly Harmless ships are easy prey in CZ's compared to all the Experts and Masters flying around. You won't find a ship lower then Competent and those tend to die quickly.
Your best defense here is to contract a crew member who will take over piloting the ship while you fly the fighter. With a higher combat rating they tend to keep your ship fairly well in one piece. The caveat is that they take a share of your profits.
Your other choice is multi-crew with someone who has fighters for you to launch. The Combat Bonds are shared fairly and you can fly a fighter generally without having to worry about the ship which is a skilled player's hands.
If you truly want a fighter experience, ditch the Keelback and go get an Eagle, Viper, or ICourier. Anything in the Small landing pad category is better suited to the classification of "Fighter" Class ships and are much more durable then the SLF's.