[Snake]

Okay-dokay. Can Golden Glow last like, 4 rounds if you use 4+M, and 5 rounds if 6+M on Power Up?

The reason is quite simple. To use it, it costs all of your Momentum (Power Up), so in other words. It makes you useless for one round, making the original duration of the skill 2 rounds, instead of 3. Skills like Charge Mind that use all of your Momentum have a rather long duration too, and in total it only costs 4 skill points, compared to Golden Glow. It's just fair it lasts at least one or two extra rounds for losing a whole turn in team fights and such.

[Noxid]

I don't think this is really necessary. Powering up is far from a wasted turn. You gain FP which is useful for sustain in longer fights. You gain KI which is required to gain access to other monk skills and strong extra effects for those skills. Not to mention monk in general is in a pretty strong place right now and doesn't really require buffs.