It'll be tough but they'll go close. They were top 6 in the East all of last season and only struggled once Rubio and Garland were hurt.
I love their roster. They've drafted well. Traded well.. And I think Bickerstaff is a good coach. They're hard to score against and have two great scoring guards.. Mobley will be a top 5 big in a few years. Allen is a great defender and lob threat. Levert can win 6th man of the year if he stays healthy. I reckon they'll lose 2nd round this year but in a year or two if they keep that team together and get some veterans, they can be a title contender.
Either way, the East is loaded because as well as those teams you listed, there's still Cleveland, Chicago, Atlanta, Charlotte etc who are all solid and tough to beat.