To me Kes was like my little sister.One that you would like to protect.
To do away with her was unthinkable. and sad.
I think that many folks felt the same way.
I wonder if we would feel the same way about her,if she stayed on to the very end.
We will never know.
Thank goodness for the three years that she was on.
I agree on your statement.
As for the question about how we would have felt about her if she had stayed the whole show, it would have depended on the storyline for the character.
However, she was brilliant during those years she was in the series.
As for the character herself, some posters have stated that she was "dull" or "meek". I disagree on that. I never found her dull in any way. In fact, one of the best things with the character was that she was both a contrast and a complement to more standard Star trek female characters like Janeway and Torres. And Kes could be tough and strong-willed too. Don't forget how she saved the ship when she stood up against the Bothan in "Persistence Of Vision". She was very brave then.
She also saved the ship in "Cold Fire", she defied the Elder Toscat in "Caretaker", not to mention that she actually left the cavse to see the sun which was brave considering the fact that it was unknown territory for the Ocampa.
She saved The Doctor in "The Swarm" and she persuaded Tuvok to go back for Janeway and Chakotay in "Resolutions" and don't forget how she fought Tieran when he had taken control over her in "Warlord".
Kes is nice and friendly but also brave and strong-willed. as such she has more depth and quality than many standard stereotype females in many series.