Kiku comes with a high price tag. Lowering its damage further starts to make that price tag seem like a slap in the face. I guess I wouldn't be horribly opposed if it come with a lowering in price of the weapon itself, but honestly, I think at 12 power it's fine. It's pretty hard to pump that past 300 damage or so, which is good but not overpowering like it was at 16 + better Wizard MA.
Not sure about it without Magic Attack Up, either. Hmm.
L40 Monk, Power Sleeve/Bracer, Attack Up: 210
L40 Wizard (LFT style), Flash Hat/Wizard Robe/Wizard Rod/Magic Gauntlet: 228
The two are fairly comparable on damage (ES starts out behind but boosts rapidly with PA), Earth is probably a slightly weaker element, and comes with 1 less vertical. The Earth Slasher has a free secondary, the Kikuer a free support ability, this probably balances.
Should they be this close? My gut is no. Earth Slash has a lower JP cost, on a more accessible job, and doesn't cost over 3000 gil per use.
The range nerf is the most interesting, although I don't think I really see it as necessary.