At the very least, we as Celtics fan know that the future is not bland - Danny Ainge did a good job not making this like the post Bird era. We have young pieces - Rondo, Bradley, Green, Sully. We aren't going to be terrible - possibly contending for a playoff spot next year if we find some decent replacements (given KG and/or Pierce retire).
I think Danny's first goal if the 2 retire is to find a 2-way big man that is effective in the pick n roll and can play solid defense (Gortat like).