Is 20k from 50 k realistic ?

I got 50k rank this year with 3 months on and off preparation, I want radio(physical challenges) but around my rank it is too costly in private I can study for another attempt as i am reading for first or second time , and hopefully get around 20 k rank next year ,which will make radio half the current cost , which i think is manageable

What are the chances of rank improvement from 50 k to 20 k ....

Or should i go for paedia or anaesthesia this year only

What should I do , confused and depressed