RF build need some advice. Thx in advance!

I am currently lv79 skill tree is

http://www.pathofexile.com/passive-skill-tree/AAAAAgEAAecEswUtBg4J9gxfDc0SaRQgFE0WbxccGJEZLho-GmwcpxzOJKon1SftKPopLitQNug26TwFPC09Dz38QYdDyEWdTP9QR1NSU6VXDVhjW6BeE18_YEthUmh0aPJxeXasfA58uIIHgseGYIzPlKCYrZrgna6ezZ_fogCnCKcwp1Wtja9stz64k7yfwGbEWMT2xq7G2M9-0iHUfNi92WHZfNpi2t3jauvu7w7vTu988B_xrPIv8kHyRfZI-ej8S_4K_lQ=

I took the defensive approach wearing Lightning Coil + Blood Dance doing purity fire + purity lightning for extra physical defense as well as lightning def. I also wear geofri's crest for extra chaos def. With this I have limited my hp to just 5k. I don't have a lot of luck with hp gear so far. I am also using brighbeak right now for attack speed with cyclone + LoH and fast leap slam. For ring I have 1 Pyre for extra burning dmg and cold + fire res.

My quesitons are:

1) worth to drop Blood Dance for boot with more hp? Or the 3% frenzy regen is a better choice for defense?

2) My original armor was using a Belly but since my armor only give me 20% ish phyical def I did get hurt but larger phyical dmg mob. Since I have EE I found that I cannot even do molten shell since the fire dmg will put mob fire resist to +25%. I had one granite flask (2 ruby, 1 sap , 1 topaz) for just in case physical. I do notice Lightning Coil made my char a lot tankier VS huge physical dmg mob. I just can't decide for now.

3) Iron Reflexes is still a good 6/7 points away. Does it worth the investment? Or I should put the rest of the points all in max life % nodes? At lv79 it is a huge investment for even 6 points to get IR right?

Is there anything I can change to improve this build? I know it not even consider decent build but that's what I can do so far... =(

thanks for all your help!

1. Blood Dance is only really for half regen maps.
2. If you can comfortably fit in Coil (preferrably legacy) definitely do it. I cba to do it usually though since I prefer to not juggle resists and use Kaom's but obviously not everyone has Kaom's.
3. I think it is waste when you have Coil.

Tree is fine, you just need more levels. Try Curse on Hit Cyclone. Drop Pyre, HP is DPS.