which motherboard for LTC mining and gaming?

Hey guys

I wish it would let me post this in the correct place. New here.

Looking to build my first litecoin rig. But I also want it to be an insane gaming computer.
I would like 4 pcie x16 slots, as I would like to add extra GPUs over time to increase mining power.
I have had a look through the forums, but couldn't find much about this. Most people seem to have dedicated mining rigs and don't use them for anything else so go for the cheapest most basic options....
I will pretty much be leaving it mining during the day, and only in the evenings using it for everything else.

So my questions are...
Which motherboard would be ideal for this?
How powerful a PSU will I need to support 4 GPUs?
Any recommendations on GPU and where to get them, as the popular ones seem to be sold out everywhere?

Finally... Is it even worth it? ASIC has destroyed bitcoin gpu mining. Could somebody create something similar for scrypt currencies?

Cost isn't really a problem right now as I have saved up 2000£ for this project, but obviously the cheaper and most cost efficient the better.

Hope somebody can help me.
Thanks