Hi pankaj, deorital will be crowded thats my personal review as have been there and witnessed it. However deoriatal to chopta trek would not be crowded at all. Infact if you will be planning to camp at tunganath you will be alone most likely.
Harshil will be same cold like tunganath…you can do harshil to bakra top trek which is not that difficult but can be tiring.
Or else you should do drive to sankri n then trek to juda lake.