@omegadoom 

Are you referring to the L2TP/PPTP connection on the router WAN? If that's the case, that is the WAN connection provided by your ISP, so you need to confirm with them, whether you should use L2TP or PPTP. 

What's more, you can only access the internet when the WAN connection is built-up successfully, I guess that's what you are referring to as per issue 1.

@Kevin_Z

Not really. For WAN connection i use only static ip. I use pptp/l2tp only if i need to have internet via vpn server.

I also have old TP-Link TL-R460 router. And i don't have any problems i mentiond with it.

l2tp works just fine and i have internet even if the router is not connected to vpn server.

The only peculiar thing is that TL-R460 has IPsek key option which is absent in Archer C6.

@woozle 

Thanks! This probably answers why there is no internet connection if connection to vpn server is not enabled. Because this router expects full config active.

Now i am a bit dissapointed by this router. Yes, it is not the preimium router but my old TL-R460 tplink router is not premium as well but it is much older.

I didn't expect that new shiny router would have reduced functionality.