In asking for a fix to this you are implying that it is happening. What if you are wrong?
I’ve topped the killboard (2nd at present) without killing former allies (so far) and with few if any starter world kills (none this season).
In my opinion you are asking for fixes to things that do not exist.
Now for your earlier suggestion of noob-farming - I have indeed indulged myself there although rarely were they actually noobs - just ill-prepared. Rex already has a fix for this in the guilty system. This cost me 9 mill creds (50% of my account balance) and a lot of RP last season.
The above said - I would not have a problem with kill cooldowns. Not that im a fan but it would be a level playing field.