I like the idea of changing a bit Gandalf, to make him fit better in the faction of Arnor
Gandalf is of course still an Istar by the time of Arnor, but he naturally has a far greater role in the following centuries of the Third Age.
He is relatively 'young' (speaking about his special and characteristic nature as an Istar) when the Witch-king establishes in Angmar (around 300 years old), and by that time he used to travel and wander a lot across Middle Earth, as all the other Istari initially did, to recollect part of his once infinite memory as a Maia, and especially to guard the World against a possible return of the Shadow in all its forms.
Gandalf, in particular, chose to travel mainly in the west of Middle Earth and to have the Elves as his most appreciated people to visit.
Anyway, all the Istari were not fully known yet by the Free People of the World, and preferred to act and operate in silence and discretion.
So, I support Gandalf being weakened a bit, both concerning his attack and powers.
I think, though, that some of his current powers are too crucial and characteristic to be changed.
His blast should totally remain, as the characteristic and basic power of the Wizards, along with his mount, given his 'wanderin pilgrim' nature; and I find also the 'Light of the Istari' very suitable for him, as he is an Istar, and capable of using a small part of his blessed powers as a Maia.
The other powers need to be changed, if we want to give him a more suitable role as a wandering counselor and support hero
And, graphically speaking, it would be better if Gandalf didn't have a sword at all, and had the AUJ/DOS staff.
