Is it still possible to develop it?
Of course bitcoin is still developing, the biggest downside of bitcoin right now is that the transaction speed is gradually improving. I think that in the future bitcoin will have many new improvements to meet the needs of the market and investors.
Can we still expect better coin than Bitcoin?
Of course, there will be many better coins than bitcoin, but the reputation of bitcoin is so high that it ranks number one in the cryptocurrency market and no other currency can surpass it.