Yes I have the same motherboard it has all the modern features. Now the thing is that the 6600k and 6700k don't come with a cooler at all so you will have to buy one anyways. So we can't skip the cooler to a later date. For how much are you getting this cooler for?
Yes a 550W is enough for today's GPUs but you never know what happens in the future. A 650W good brand PSU will last you possibly 10 years so don't save money on this it's hardly going to be 1k.
If you want to go NV you have to wait for the GTX 1060. Go for whichever is cheaper between RX 480 8GB and GTX 1060. If they are same price then go for whatever you prefer. But buying a GTX 970 is simply a really bad choice now so we have to wait. Both the cards I mentioned have been launched in international market already so they should be here anytime soon.
So unfortunately we are not able to save money but remember with the i7 build that I am suggesting every single component with last 6-7 years apart from GPU. And about the last part you need to know that it is difficult to predict how long a GPU is going to last. If you are okay with playing games at medium settings then a GPU can last 4 years but never at maxed settings. So with this build if you upgrade your graphics card after let's say 3 years then your system will easily give you total life of 6-7 years with only the added expense of a GPU in between.
If you really wanna delay an expense you can buy the SSD later but remember you will have to install windows again so that's the hassle of not buying the SSD in the beginning. If you are okay with it then sure you can delay that. Since you care about the long term aspect of your PC I would even suggest to splurge for a 480GB SSD as games are getting bigger and bigger. But of course you can always buy a second SSD in the future so this isn't necessary.
I know this all may sound like excessive expenditure but with the current state of PC hardware, by going big in the beginning you will save money in the long term.
M clear now Bro. Major investment: CPU MOBO
I will go for 6700K+Z170-K
Cooler i will try to find some air cooler by CM.
PSU I guess CS 650 is fine as its Gold 80Plus
I will go for SSD 240GB
I will only wait for New GPU to be released. New series would be good and more lifespan but just say lil wait is worth it.
RAMs simple ones are okay aswell
Thanks alot Bro. relevant and appropriate guide to my issue