Help With WandMara Build Please.

I was watching Build of the week earlier and i saw the BM wand mara, and he looked really fun so i tried to make a BM Irongrip wander.
Feedback would be great and any ideas to streamline it.
The idea is to make a tanky wand mara who uses some skill (frenzy, power siphon. But im open to ideas) and to decent damage.

http://www.pathofexile.com/passive-skill-tree/AAAAAgEAAecFLRQgFHEUsBkuGlUc5x0UIPAlvCftKPopVDGeMn41kjbFNug26TpSOuE_c0CgQYdBqkTnRmlKmkrITeNQR1BQVElVxlcNWGNYr18_YEthIWSjaHRqHmo7bqpyqXTteA14znrvfNmCx4TvhymHnozPj0aRzpuhnrmezZ_LoLSmV6cIpzCoGKlurJisqrXytz64k7ndu-3EFcT2xtjPZdDQ0PvSIdMb2CTZYdrd2wLfv-Nq51Lr7u8O8i_yRfZI99f56PrS-6r8ZP4K_o8=

Just out of curiosity: why would you invest into Fusillade ("6% increased wand damage per power charge") with resolute technique and no power charge taken from tree?

And is it worth it to invest 4 points for the Holy Strength ("3% increased buff effect") life node?

Elder Power and Wandslingers Prowess look pretty sexy to me? Why not going for them?

Hmmm like i said, i'm not the best at this :D. looking at those suggestions i could get rid of those passives and reach the elder power in the same skill points, i thank you for pointing that out, any other ideas would be great.
new build btw
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