auto connect to regullaly visited locations: twc hotspots, Starbucks, work and soon metro(wifi in the future) 2dBi mid-range input antenna @ 2.5GHZ & Output @ around 150 mbps install openvpn power by battery pack
Future upgrades:
touchscreen 4" for fast wifi connection with new locations
so far bought, other things i already own (sd card, powercord, usb, dmi, powerbox)
Might I suggest a different portable computer? like an ODroid. The Pi is kinda shitty. That and I would opt for a different wifi chip. See if you can find an Atheros or Intel. AVOID broadcom
You might consider installing a DNS server on it which the client devices will use when connecting. While you can configure opendns or google or whatever in the DHCP having a DNS server on the device will allow you to guarantee that the DNS traffic goes over the VPN. You could also install DNScrypt on it for extra protection.
Another idea is if this VPN device is connecting to a VPN service like PIA or something, but you also have a home server running a VPN you could configure it with two VPN connections, one to the home network and the other to a VPN service. Then configure the routing table so that traffic to your home network will go over that VPN and everything else will go to the other VPN (for internet access). This way not only do you get secured internet access but you also get access to your local resources at the same time. I do something similar with a VPS.
You can make a router run very well on a PI, just dont allow it to start into GUI upon boot and you're more then golden. Got a similara project running here at home, if you need some help feel free to ask for help.
I was just trying to tell you that the pis are slow as fuck... And have rather shitty documentation in comparison to the beaglebone blacks and the odroid which are so much faster
Uhmm also the best term for your project was not a router but either a wireless access point or wireless hub. Seeing as this project doesnt require having a switch built in with different vlans for wan and lan+wlan