Switching from MAg to ALm will be a great weight penalty... 150lbs IMO... With addition of all the other upgrades 200lbs wouldn't be farfetched to me
Not exactly a great weight penalty over 26500lbs. Get rid of three of the six FG's if you really want to save weight, as they don't make much difference anyway. Alternatively take approximately seven minutes less fuel, either way it is not going to be a huge show stopper.