Except for the fact that the rogue levels grant access to UMD and trap skills there is no real reason to take rogue levels on a Half elf build that already has 12 monk levels (improved evasion beats evasion from rogue levels) and a number of fighter levels (fighter grants access to haste boost as well) and that is already taking the Rogue Dilettante for a tasty 3d6 SA damage.
2 Ranger levels results in first tier of TWF as a bonus feat, Bow strength and Rapid Shot as bonus feats, +3 damage to a single type of favored enemy, wand usage, and 35% sprint boost.
And chasing after Paladin Dilettante requires 13 CHA, and your suggested start only has 12. This results in mandatory feat swapping later.
Code:
Character Plan by DDO Character Planner Version 3.8.0
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Level 20 Lawful Good Half-Elf Female
(6 Fighter \ 12 Monk \ 2 Ranger)
Starting Feat/Enhancement
Abilities Base Stats Modified Stats
(32 Point) (Level 1) (Level 20)
Strength 16 23
Dexterity 15 18
Constitution 14 14
Intelligence 10 12
Wisdom 14 15
Charisma 8 8
Tomes Used
+2 Tome of Dexterity used at level 7
+2 Tome of Intelligence used at level 7
Starting Feat/Enhancement
Base Skills Modified Skills
Skills (Level 1) (Level 20)
Balance 4 15
Bluff -1 0
Concentration 6 28
Diplomacy -1 0
Disable Device n/a n/a
Haggle -1 -1
Heal 2 2
Hide 6 25
Intimidate -1 0
Jump 7 15
Listen 2 2
Move Silently 6 25
Open Lock n/a n/a
Perform n/a n/a
Repair 0 1
Search 0 1
Spot 2 2
Swim 3 6
Tumble 4 14
Use Magic Device n/a n/a
Level 1 (Ranger)
Skill: Balance (+2)
Skill: Concentration (+4)
Skill: Hide (+4)
Skill: Jump (+4)
Skill: Move Silently (+4)
Skill: Tumble (+2)
Feat: (Favored Enemy) Favored Enemy: Undead
Feat: (Half-Elf Dilettante) Half-Elf Dilettante: Rogue
Feat: (Selected) Weapon Focus: Bludgeoning Weapons
Enhancement: Ranger Sprint Boost I
Enhancement: Ranger Favored Damage I
Level 2 (Monk)
Skill: Balance (+1)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Feat: (Monk Bonus) Power Attack
Enhancement: Human Improved Recovery I
Enhancement: Improved Jump I
Enhancement: Improved Tumble I
Level 3 (Monk)
Skill: Balance (+1)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Feat: (Selected) Sap
Feat: (Monk Bonus) Toughness
Enhancement: Way of the Patient Tortoise I
Enhancement: Racial Toughness I
Enhancement: Monk Wisdom I
Level 4 (Monk)
Skill: Balance (+1)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Feat: (Monk Path) Path of Inevitable Dominion: Fists of Darkness
Enhancement: Monk Improved Recovery I
Level 5 (Ranger)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Jump (+3)
Skill: Move Silently (+1)
Enhancement: Improved Rogue Dilettante I
Enhancement: Human Adaptability Strength I
Enhancement: Ranger Dexterity I
Level 6 (Fighter)
Skill: Concentration (+1)
Feat: (Selected) Stunning Blow
Feat: (Fighter Bonus) Zen Archery
Enhancement: Fighter Attack Boost I
Enhancement: Fighter Haste Boost I
Enhancement: Fighter Critical Accuracy I
Enhancement: Racial Toughness II
Enhancement: Fighter Toughness I
Level 7 (Fighter)
Skill: Concentration (+1)
Feat: (Fighter Bonus) Quick Draw
Enhancement: Fighter Strength I
Level 8 (Fighter)
Skill: Balance (+0.5)
Skill: Concentration (+1)
Enhancement: Fighter Strategy (Stunning Blow) I
Level 9 (Fighter)
Skill: Balance (+0.5)
Skill: Concentration (+1)
Feat: (Selected) Improved Two Weapon Fighting
Feat: (Fighter Bonus) Weapon Specialization: Bludgeoning Weapons
Enhancement: Fighter Attack Boost II
Enhancement: Fighter Haste Boost II
Enhancement: Fighter Critical Accuracy II
Enhancement: Fighter Strategy (Stunning Blow) II
Level 10 (Monk)
Skill: Concentration (+1)
Skill: Hide (+2)
Skill: Move Silently (+2)
Enhancement: Static Charge
Enhancement: Improved Jump II
Enhancement: Improved Tumble II
Level 11 (Monk)
Skill: Concentration (+1)
Skill: Hide (+2)
Skill: Move Silently (+2)
Enhancement: Way of the Patient Tortoise II
Enhancement: Fighter Toughness II
Level 12 (Monk)
Skill: Concentration (+1)
Skill: Hide (+2)
Skill: Move Silently (+2)
Feat: (Monk Bonus) Dodge
Feat: (Selected) Improved Critical: Bludgeoning Weapons
Enhancement: Monk Ninja Spy I
Level 13 (Monk)
Skill: Concentration (+1)
Skill: Hide (+2)
Skill: Move Silently (+2)
Enhancement: Fists of Iron
Enhancement: Adept of Rock
Enhancement: Adept of Flame
Level 14 (Monk)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Skill: Tumble (+2)
Enhancement: Adept of Wind
Level 15 (Monk)
Skill: Balance (+1)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Skill: Tumble (+1)
Feat: (Selected) Greater Two Weapon Fighting
Enhancement: Improved Rogue Dilettante II
Level 16 (Monk)
Skill: Balance (+1)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Skill: Tumble (+1)
Enhancement: Porous Soul
Enhancement: All-Consuming Flame
Enhancement: Winter's Touch
Level 17 (Monk)
Skill: Balance (+1)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Skill: Tumble (+1)
Enhancement: Touch of Death
Level 18 (Monk)
Skill: Balance (+1)
Skill: Concentration (+1)
Skill: Hide (+1)
Skill: Move Silently (+1)
Skill: Tumble (+1)
Feat: (Selected) Weapon Focus: Ranged Weapons
Enhancement: Monk Ninja Spy II
Enhancement: Master of Bonfires
Level 19 (Fighter)
Skill: Balance (+0.5)
Skill: Concentration (+1)
Enhancement: Master of Thunder
Level 20 (Fighter)
Skill: Balance (+0.5)
Skill: Concentration (+1)
Feat: (Fighter Bonus) Weapon Specialization: Ranged Weapons
Enhancement: Kensei Unarmed Mastery I
Enhancement: Fighter Kensei I
Enhancement: Half-Elf Improved Trap Sense I
That would be a somewhat improved version of what you are trying to make in my opinion. It probably could use a couple more improvements. But it should hit a heck of a lot harder. I only included the two tomes I used to make it work out. Honesty one could probably do with additional tomes for STR, CON, and WIS. But they don't make or break the build. And you could skip the INT tome, but you'd lose 13 skill points from the build.