Build Version
0.7.7F … 1st Ver.
Video: (at level 78, in 0.7.7F)
Main skill (in 0.7.7F)
Devouring Orb (1.5～3 k dmg / crit hit) and
Abyssal Orb (～0.5 k dmg / crit hit)
Void Waver Guide (Beta 0.7.7F)
pros/cons
・pros
High DPS
High healing effectiveness.
Not important of unique items / idols so much.
・cons
Substantially, close-ranged combat style.
High healing effectiveness is useless to 1-shot.
Unique gear / Idols
Option 1 : Decayed Skull, Unique helmet
Decayed Skull - Unique Dome Cap - Helmet - Last Epoch Item Database
Option 2 : Introspective Ornate Solar Idols (Recommendation 1～2)
Mana Efficiency With Void Spells - Item Prefixes - Last Epoch Item Database
If you do not have " Introspective Ornate Idol", please cast Volatile Reversal every 3 Devouring orb casting for keeping Mana.
The more you have this idols, the easier it will be to Mana manage.
Synergy / Explanation
Perhaps, for the caster type, the increase in echo spawn rate is not so important, and it seems that it is not worth spending a lot of skill points.
Here, I paid attention to Paladin’s “increased spell crit chance” passive skill and aimed at high damage by combining it with devouring orb.
As a result of choosing Paladin, naturally it is difficult to increase increased void damage, so I aimed to increase damage by securing a large amount of Attunement.
Therefore, the defense is protection style.
If you don’t have enough “chance to receive a glancing blow”, “+ dodge rating for 4 seconds on potion use” may help. (My current state 
)
Stats (at level 78)
Non Buff
※Dodge rate increase to around 60 % while 4 sec by using potions.
Current gears
Need “Critical strike chance” affix on Weapon, amulet, and rings.
Maybe, Stun chance is also useful.
Passive tree (at Level 78)
Sentinel
Void Knight
Forge Guard
Paladin
Active skills
1 Devouring orb (main skill)
Abyssal orb (Devouring orb’s Spell) is fun, but maybe it does not scaled by Attunement.
So learning Dark Moon is the best for dealing high damage than learning Dark Torrent (Abyssal orb frequency +).
2 Ring of shields (for defense)
3 Holy Aura (for Buff)
4 Sigils of Hope (for Buff)
5 Volatile Reversal (for Mana management)
Thank you for your interest !