2 handed mace - lightning strike build - something different with IRON GRIP.

I would like to ask on opinion on this 2 handed lightning strike build.

I am planning to use 2 handed mace together with Lightning strike. Its little bit different than most of the build which I can see, because I am going to take iron grip and other 30% elemental damage. I will be pleased for any advice.

Iron grip should give me about 60% - 70% damage increase to lightning strike and I am counting just nodes (little bit over 300 STR from nodes) Its projectile damage so it should benefit from it, at least I hope that it will benefit from it :-)

90 points build
http://www.pathofexile.com/passive-skill-tree/AAAAAgUBAnEEswVbCygOPA9UD8wUIBRNFHEZLhnpGjgn7SlPMgkyfjKJNro6UjrYPC1BP0GqRHJG103YUEdR5lWpVgRX4lg9WfNfqmCIYVJs9m6qcqlz4Xflerh82YErgpuC5ITEhmCKdIqvi4yMdpARkFWUh5e0nsWiAKZkpzCnhKlorKqsuq6TtC-3PrndwBrE9sauyZjUj97B37Lfv-Fz5K3sOO0g7w7wH_Iv8pzz3fcy94j3vvjr

111 points build
http://www.pathofexile.com/passive-skill-tree/AAAAAgUBAnEEswUtBVsLKA48D1QPzBQgFE0UcRkuGekaOCFgJ-0otSkuKU8yCTJ-Mok2ujpSOtg8LT38QKBBP0GqRHJG103YUEdQUFHmValWBFfiWD1YY1nzXz9fqmCIYVJs9m6XbqpyqXPhdPF35Xq4fLh82YErgpuC5ITEhmCKdIuMjAaMdozPkBGQVZSHl7ScJ565nsWgnaIApKymZKcwp4SpaKyqrLquk7Qvtz653cAaxPbGrsbYyZjUj97B37Lfv-Fz5K3sOO0g7hTvDu9O8B_yL_Kc8932SPcy94j3vvjr