I have mixed feelings about it...
My feelings about my karma:
Having a positive karma for me shows that ppl see me as i am, and gives me a feeling of achivment that ppl think positivly about me.
Having a bad karma in the other hand doesnt disturb me. I dont have that feeling like above, and i just ignore it. these are the times when i dont care about karma, because i know im not a bad person.
My feelings about others karma:
I dont judge anyone by karma at all. I have to see it for myself if they really are bad or not. I have many friends who have negative karma and it doesnt bother me at all, because i know they arent bad.
And as for it having an option to remove it: meeeh. It wouldnt be fair i guess. If you think about it, there are and always will be "trolls" and they do deserve a bad karma... and if there is an option to turn it off... they will just troll and not get the bad karma they deserve.
Or if someone helped you greatly or something... you couldnt praise them for it... because their karma is off. While you desperately would want to give something.
As for biting and nuzzling:
I never bite anyone without a reason(and these have to be really good reasons). I have bitten 2 or 3 ppl so far because of their offensive replies/posts towards me. Though i do agree that targeting someone and biting them every day is wrong, i did bite a person 2 or 3 times because of their highly offensive comments about me...
However i do nuzzle without any reason. I just go on the forum and nuzzle a few ppl, even if i dont know them. I respect everyone and i want to show it this way. Even though you never know who nuzzled you. Plus if someone leaves a lovely comment, or stands on my side in an argument or am friends with... i like to nuzzle them daily XD
As some already have stated before me, biting can be a good "punishment" for those who do something wrong against you or their reply is offensive. Not that many care, but it calms you down a bit. Its really tiring to write 4-5 rows.. while you can just click one little word.
All in all: i voted no.