What it says on the tin. Give Monks UD, either at level 4, or even as a capstone at 8 (these are the two levels at which Monks receive no additional feats). It makes no sense thematically or mechanically they don't get it.
HERESY I hear you call. MONKS ARE STRONGK
Yes, because they're MAD, monks can get buffed to high heaven, this is true. Except because of their lack of UD, they can and will lose ALL of their ac to a shuffle step, barring any barks or mage armor. Monks are entirely situational, strong only in very specific situations where they've had time to buff or get the element of surprise. Their battlefield role as a high mobility attack spanner means they will constantly be butting up against NWNs engine limitations and the dreaded shuffle step.
If it is the weaboo you fear, do not fear them. I trust our community to continue producing just as many high quality monk concepts as they do now. Which is to say, almost none, because nobody plays them, because MAD melee with 3/4 ab prog
Also, anecdotes about how you made a totally badass monk x chapters ago with DM loot and a bag full of potions and alchemy goodies do not fully refute my suggestion, at least not on their own, though I will certainly bow to the knowledge of the more mechanically experienced on this.
I am not currently playing, nor plan to, a monk
While I would like this to happen (as to make Dexterity monks a more viable choice in comparison to Strength monks), I will point out that monks gain an increase to Improved Unarmed Strike damage die size at levels 4 and 8.
Those are not empty levels for monks.
Rogue/monk or monk/assassin is common way to get this extremly useful feat for monks but I do not think what such combinations is easy to play. I am always felt what EFU is mostly for pure classes(all this perks!).
Increasing damage die not helps greatly for dex monks. Together with few stances it can help to nearly one-shot few weak monsters but anything with 5 or 10 DR monk going never to harm unless monk have special gloves with bonus elemental dmg. Or pocket wizard.
Perhaps giving this feat for pure monks at 8th level?
I would be fine even receiving it at lvl 8 for pure, yes. A 3 rogue dip is an entirely too tempting prospect for a monk, giving them huge flabking dmg and UD.
And yeah, 4 and d 8 are dmg dice levels for monk. They are the closest thing to empty levels o could find though
It should also be noted Stunning Fist was nerfed for EE
I'm not averse to Monks receiving it at 8
Uncanny Dodge does let you retain your dexterity bonus even if caught flat footed or attacked by a hidden / invisible creature per the wiki. This is an important thing, especially for a monk that does use potions such as cats grace. It means that a monk loses anywhere from 2 to 5 AC (assumes most monks have a Dex of at least 14 without potions) when caught flat footed. I think level 8 as an added perk is a very reasonable place to give this. It would not be a huge power creep but it would fix one of the more irritating aspects of playing a monk.
Where this really becomes an issue in my experience is a monk trying to close the gap or move around in a battle against massed range attacks. For instance if you have ten or so crossbow armed kobolds shooting at you as you move around the field, your not in direct combat so your considered flat footed from a mechanics standpoint. That is where the AC hit has been a killer.