1. You won't have enough mana with 24 intellect and no mana regen nodes to spam lightning Strike, that's for sure.
2. Why did you take so many speed boosts nodes. Are you going to kite and LS? If so a bow Lightning Arrow would work probably better. But even so, you don't need so many speed nodes, and especially not so many little 3% nodes. You got 70-80 points, you want the get the most ouf of them.
3. Same goes for Attack Speed, a 3% node is just NOT worth spending in, let alone 3+. There's an attack speed support gem that gives 25% at lvl 1, THAT is worth it.
4. Your HP looks ok, although you again took too many 8% nodes that are probably not worth their price. Try to get more +flat HP boosts, those work better with the % nodes.
5. Resistances and especially armor/evasion/es, or whatever gear based defenses you use are nonexistent. There are 3 nodes, worth 52% armor very close to the starting area, those will make your game much smoother in Cruel+.
is what I could came up with in 10 min. It's not polished, but could work. I took a Resolute Technic solution to the accuracy problems, since it's much more reliable with LS. The next set would be to go all the way up, 10 nodes away, and get Static Blows to help LS even more. The good part, I think, is that the spec is make around any 2handed weapon, so you have a wide variety of things to choose from. If we wanted to go into a specific weapon, mace would probably be better, since there is a 18% node 1 point away in the templar zone.
I took both Armor/Evasion nodes for defense, since I had in mind an armourish/dodgy duelist.
I also took some Endurance charge nodes, but those are experimental, It's possible it will be very hard in Merciless still, so Enduring Cry skill and gain 3-5 endurance charges would make your gameplay much more enjoyable.
Molten Shell is also probably a must have, and Blood magic support gem for LS. Keep mana for molten shell, leap slam(mobillity) and enduring cry. If mana is not enough, there are a few 30 intellect nodes close by.
As for elemental resistances, there are good i think. 60% for all 3 of them, that will get you to atleast 0% once you enter merciless.
But in the end, the build is more of a guideline, you actually have to spend points where you need them most and when. If you end up with 50%+ armor early on and keep it that way, it's safe to drop a few armor nodes from the marauder zone, etc.