Wouldn't the logical replacement in the starting lineup for Bradley be Hayward?
A problem with this is IT will then be forced to guard the oppositions PG, as Hayward probably isn't quick enough to guard quick guards, Having Bradley and Smart has helped to IT on defense, now we only have one defensive backcourt stud.
Also if we start small with Crowder or Morris at PF, then Smarts lack of shooting touch won't crush our spacing as much as it would have with Amir on the floor last year.
This is not a problem at all. The talk of hiding IT on defence is hollow. Bradley used to guard the pg position because it was his
elite skill. Isaiah can defend the pg position adequately for our system. It will require improved help defense from the bigs which we should get given we have become younger and more athletic in that regard.
Smart is best covering the 2 guard anyway, where he can play help defense.
That is his elite skill.
Hayward at the 2 also causes huge match up problems at the other end of the court which will greatly reduce the pressure on Isaiah.
On your second point, I believe that Baynes is going to fill the Amir role. Morris or Smart will come in at the end of the game to give our best lineup but Brad has consistently shown that he wants to keep Horford away from the battering in the post. Given his injury history it makes sense as well.