Hi,
I'm new in Photography and learning . I bought myself a Canon EOS 60D with twin lens kit 18-55mm IS and 55-250mm IS 6 almost 6 months. I do like taking portrait and sometimes in low light. Now a days i'm feeling i need a mid range lens that will cover a bit of distance and will not compromise with focus, speed and quality of photos. i need to swap lens most of the time.
still i can fit that in my budget .
Would you please help me to choose a good lens that will cover my everyday photos , of-course in budget. i can spend upto $1000

Please post your advice and suggestions ...
Will really appreciate your help.

thanks
John