कमाल आहे!

Yes! You can say 'To kamaal aahe' (He is amazing). It's a very common way to describe a talented person.

Use it sparingly. It's better to use it when praising the company's achievements rather than using it as a general exclamation.

'Kamaal' is more about wonder and disbelief, while 'Bhari' is more about quality and 'coolness'.

Yes, if the weather is extreme (like very heavy rain), you can say 'Kamaal aahe ya पावसाची!'

It is a loanword from Persian/Arabic, but it has been part of Marathi for centuries.

Say 'Kamaal kelis!' (informal) or 'Kamaal kelit!' (formal).

Absolutely! 'काय कमाल सूर्यास्त आहे!' is very natural.

The word 'Kamaal' itself doesn't change, but the pronouns around it might (e.g., 'Tujhi' vs 'Tujha' depending on the implied noun).

It depends on your relationship. With friends, it's funny. With a stranger, it might be seen as mocking.

There isn't a direct single-word opposite, but 'Kahi khas nahi' (Nothing special) is often used.