Option 2 looks nice, but you missed that the shield is not yet a magical weapon (it only _acts_ like a +1 weapon, but it needs to truly be one to get magical enhancement).

So you need these changes to make it legal :
10th +1 bashing/+1 spiked heavy wooden shield
13th +1 bashing/+1 brutal surge spiked heavy wooden shield

Dunno exactly what 16th should be, in principle he could get +3 to AC for a +4 bashing/+1 brutal surge shield with a menu E armor enhancement ... but you gave him ability enhancement scores slightly earlier than normal, so probably a little less to compensate. Personally I'm not a big believer in adding enhancement bonuses to weapons/armor higher than +1 ... that is what Magic Vestment and GMW is for. How about giving Greater Blurring (a +2 enhancement) so :
16th +1 bashing, greater blurring/+1 brutal surge spiked heavy wooden shield