[2.4] Non-crit flexbile BL Elementalist EO+CI

+Pretty good dps for BL
+Decent clear speed
+Reflect viable
+Fun and easy
+Atziri and most of red maps viable (although some bosses like Uber Izaro are taking some time without 6l)
+Pretty safe thanks to flasks and blind, 9k es on 90lvl! (no one-hitting, even safer with Decoy Totem)
+Although full potential is unlocked with around 10ex, can be still viable without Heretic's Veil and 6l Pledge

-Mods with BM or -max res with ele reflect combo are impossible
-DPS potential of BL is far from the best possible in-game, so killing the strongest bosses in game could be troublesome (T14+, especially on 5l)
-Bosses without any minions might give a mana problems without (drop curse for Clarity if necessary)

Can be 5l. I chose Pledge, because BL's lack of dps. Making it up to 7l helps provides enough dps to kill fast almost everything.

This is not mandatory, but greatly helps when you want even more safety or dps - whether
you chose Conductivity or Enfeeble/Temporal Chains, it's up to you.

Focus on ES, res, mana (and mana regen), strength, dexterity and cast speed. You might increase es with Energy from Within (look at my tree). I also focused on faster recharge rate for less kitting and more facerolling (as much it's possible).

For rich people: Vessel of Vinktar.

BL-Controlled Destruction-Slower Projectiles-Lightning Penetration-Added Lightning-Faster Casting
Orb of Storms-Innervate-Culling Strike-Blind
Lightning Golem-Flame Golem-Minion Life
Warlord's Mark-Blashphemy/Heretic's Veil
CWDT+IC
Discipline for CI ofc (I also recommend Vaal Discipline for emergency)
Free choice for movement skill, I chose Flame Dash, because it takes less sockets

https://www.pathofexile.com/passive-skill-tree/AAAABAMCAAMeDXwOXBBYEQ8RLxFQEzUV1xbzFy8XpBhqGyUdFB3ZH0EfxyL0JjwpTysKK3gsnCy_LYsvnTW5Ow08BT1fQ1RFfklRSbFLrkyzUEJSU1M1VEdV1lZIVmNXlFgHXGtd8l8qX2pk52ZUZp5q-mt6bAttGXRVdhF4L3zlfq9_xoCkgpuESIV7hq6IQow2jHaNGY9Gj_qQ-pMnl5WX9Jo7m6GePJ7En9-hL6a-pwinK6yYtAy3Mb6KwGbBxcNtyL_K09Af0NDUB9Wm18_YJNlb2V_cjd2M323fiuAS6QLquuwY7DjvfO-I7-vw1fRx99f5N_rS?accountName=Gosen&characterName=Electronella
+kill all Bandits (or get cast speed on Cruel)
Start ascendancy with Golems or Pendulum, then Paragon. Uber not mandatory, but can help proc Onslaught.

Up to 19-20k dps with 6l with almost all gems maxed out, golems and all other buffs (Atziri's flask). You should easily reach over 10k with 5l, golems and EO. It's really good value for this skill, so don't worry. I have around 10k dps without EO and Onslaught, but in action without much problem it goes up to around 14-17k.

Screens for non-Pendulum, Pendulum buff and fully buffed with EO, Onslaught and Flask:

I chose pure CI. You can try hybrid, but I prefer that way. Stun could be a problem, but passives from tree and IC should be enough for worst scenarios. Although we can reach around 7-9k es, it's our only defense, so don't neglect Basalt or Granite flasks, they really help, especially with Alchemist passive. Personally I chose to focus on faster ES recharge, since we don't have shield and lose lot of potential es. I don't have to kite a lot against weaker bosses, just use flask and leech, blind and faster recharge should do a thing. For stronger bosses I use Decoy Totem, but the stronger bosses (T14+) are killing it really fast, even with resistance support.

Usual stuff. Lifesprig, Tabula, Atziri's Foible, Dream Fragments, Asenanth's Mark or everything you think might help you. Should be fine if you start using BL as soon you get it. For new game you can start with Freezing Pulse and then move on to Spark/Arc.

Don't worry about elemental reflect and hex proof maps. In first scenario drop second curse for Purity of Lightning. No sweat, unless really big pack of mobs, but Topaz Flask gives almost 100% safety anyway. You should be fine with Ascendancy passive and leech. For second scenario drop curses for maxed out Clarity and Wrath/HoT. With hybrid build and Shavs you can add more auras (BM support), for example Wrath, increasing dps even more, but note that without shield es loss from armor will be huge, unless you're rich and can afford 250+es gloves and boots. You can also experiment with Orb of Storms links and few free sockets instead of Decoy Totem.

No need to add increased area effect gem to BL, because of passives (I tried adding support gem, but I didn't feel it's necessary, so I dropped it permanently), so dps potential is even greater, especially with Pledge. Orb of Storms helps with Elemental Overlord and gives Onslaught, which not only increases our dps but greatly improves clear speed. Culling Strike helps trigger Onslaught as Orb of Storms itself won't kill mobs too often. Conductivity increase our damage and also helps with procing Onslaught (hence Shaper of Desolation). Even with CI I wouldn't worry about Occultist. 7-9k es should be enough. The Elementalist ascendancy gives lot of dps thanks to increased damage and golem buffs.

No experience and software for that, but I made a single one to show you that even noobish and reckless gameplay on ele reflect and ground effects affecting ES the most is doable on red map:

Don't try this at home: How to not play PoE