There are so many storylines over the years that stick with me.
Donna was always one of my favourite receptionists- I didn't really like how they got rid of her, she was very ditzy and it seemed a bit out of character. Though not, I guess she was sticking up for her son. But she risked her job. But completely changing characters is a very Doctors thing to do to people. Gobby's accident and her change from a 'comedy' character to pretty annoying and miserable was not welcome though- but their constant house moves were funny
.(She wanted a conservatory!)
I never liked Val (as long term posters on this thread will know) when she first arrived, but she grew on me over time.
I loved Heston and his bow tie- yes, that Christmas cliffhanger was horrible, and the way they killed him off 
.
Loved George and Ronnie, who are of course a RL couple.
Juuuuuulia and her annoying grandaughter and useless son.
They've had some very wtf stoylines - and I didn't mind them really, the tadpoles in handbags.
Some very sad episodes too. (Dr Nick getting runover was bloody hilarious though).
I loved Elaine, and her necklaces of doom. I'd haver liked to see her back for the last episodes, along with Mrs T . But loved Mrs T got her ending with the Rev.
Annoyed they never picked up on the 'date' Al had just before he was attacked- they had real chemistry, andsurely she would have tried to track him down? He was great with Niamh -her 'exit' story was bananas though.
Just too many things .