Right now, the best shield in the game is Levik's defender.
A 18 fighter/2 paladin can raise its Maximum Dexterity Bonus to seven, nine with Stalwart Defender which you only gain out of if you Dex is higher than 24.
Assuming high Dex (but still Str-based):
15 base
+6 item
+4 tome
+1 profane
26
Then, maybe there will be some Exceptional Dexterity II item in M9, for 28 Dex and the +9 Dex modifier. Only elves, drows and halflings could go that high without sacrificing too much, but going non-dwarf represents a loss of 2 AC because it is the only way to hit a MDB of 7 with a Dragontouched fullplate (and it represents a lot of APs!).
Maybe M9 loot will make this possible, but it's only speculation.
Right now, S&B gains as much AC than non-S&B out of Stalwart Defender.