Router VPN decryption too slow

I have seen the tek syndicates videos (pfSense: How to Turn an Old PC into an Epic Router and INBOX.EXE 0035: Build Your Own Router & Nas - pfSense and FreeNAS) along with having done some searching online. However I do not believe anyone is as crazy as I. Recently I purchased the 1 year subscription to PrivateInternetAccess and set it up on my Netgear nighthawk r7000 but the speed at wich it decrypts limits my 40Mb/s connection to roughly 15Mb/s. While 15 is still nice, It would be great if i could speed it up.

So the plan is, if possible, to use an old computer as either a modem or a bridge between the router and modem to do the vpn encryption. Another issue is that the nighthawk has an amazing range and I would prefer not to use the pc as the router. I have no idea if this is possible and would like some thoughts. 

If you have any browser plugin like "https everywhere" running your encypted vpn connection will be slowed down substantially, well thats what happened to me anyway.

Also if there is an option for different vpn encryption levels the higher it is the slower your speeds will be.

I am running on default settings, minimum for an encrypted connection, it is just that the router is not fast enough for the entire household.

So what you're trying to do is to speed up the VPN connection while still having awesome WiFi from your current router.

So yeah. Use an old pc like you're saying as a router via PFsense with the vpn and then turn your current router into an access point for the WiFi.

Hint: disable the DHCP server and don't use the WAN port on the router. Have a network cord going from the old_pc/pfsense router to the integrated switch on your current router.

Alright, good. I just wanted to make sure it was possible/ not a horrible idea before i did this. Im going to have to get an Ethernet card as the current old pc only has 1 RJ-45 port. Thank you though, ill post back here whenever the card is here and i try it out.