ne10g

https://www.speedtest.net/result/c/70b7fba8-602e-45db-8fdd-ac4296c93cc1
 
 

Essentially the issue is ah his end, the source. So whatever you do at your end will make little difference, the problems are with his initial connection to the web.
 
However...that may not mean there is nothing that can be done. Some things to consider (which actually you are kind of almost getting at)
 
Where does he mainly need to connect to (end point) Is there a better route to this end point?  
For the above, the way to look at it is. Your friend connects from his ISP (source) and ultimately struggles with slow speed at somewhere down the line (end point) so he wants to find out is there a better route to take to get to the end point. Think traffic in a city, taking another route to get to the destination faster.
 
A way he could try quite easily is a VPN. The connecting to different locations (services provide lots!) and see how it performs with each.
 
Have a look for some free trials of different VPN services before spending any money as it may not help and it could be that his ISP just had crappy routing to everywhere no matter what! 

check out speedify - I've used it in the past and it works well. It will combine multiple into one, very cheap as well really.  this iwll give you true double speeds as well rather than load balancing etc.

forget wifi for a moment, plug a machine directly into the router with ethernet cable, do a coople of speed tests, what do you get?  If this is bad, then the issue is at least not wifi, if this is good, then next step is to tacle the wifi issues.

Yea it can be virtualised but you are not going to get 10Gbit throughput from a virtualised network interface.  You will have to use PCIe pass-through for the network interface(s) to reach that and place the interface in the dataplane

Build a custom TNSR installation, its free now for home/non-commercial use.  This is what the pfSense guys have been working on along side the pfSense project but uses a different way of handling traffic using VPP (Vector Packet Processing) and DPDK (Data Plane Development Kit) to minimise CPU cycles.  These are developments on Linux to substantially improve per core packet processing capability.  From around 1Gbit/s per core to around 10Gbit/s per core.
 
https://www.tnsr.com/
https://www.tnsr.com/tnsr-vs-pfsense-software
 
Can do 10G with ease, I would probably use Intel 10G, Mellanox Connect-X or SolarFlare cards in the installation.  Can pick them up pretty cheap, I'm using a SolarFlare SFN5121 in my colo/test chassis running TNSR.

Has no GUI, but does have a REST API and console access, can get it setup for normal internet usage pretty easily and may teach you something new.

As I patiently wait for my 10Gbps upgrade I have to struggle along with this...

Good God man, you don't need anything even remotely as powerful or expensive as what you proposed earlier in the thread.  You're getting a lot of information from folks that have no real world, direct, hands-on experience in the subject.  So take care in what you read on the Internet.  My router is a small Intel G4400 build that has 2 built-in GigE interfaces.  To that I added a single 2x10GigE NIC into its only x16 PCI-E slot.  And, I'm running FreeBSD, which is the basis of pfsense.  Also using pf for filtering and NATing as needed.
 
IOW: I've built a pfsense box without downloading pfsense.
 
Can I get 10Gbit/sec through it with that pitiful little CPU?  Yep:
 
- - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 5.42 GBytes 4.66 Gbits/sec 0 sender [ 5] 0.00-10.04 sec 5.42 GBytes 4.64 Gbits/sec receiver [ 7] 0.00-10.00 sec 5.43 GBytes 4.67 Gbits/sec 0 sender [ 7] 0.00-10.04 sec 5.43 GBytes 4.65 Gbits/sec receiver [SUM] 0.00-10.00 sec 10.9 GBytes 9.32 Gbits/sec 0 sender [SUM] 0.00-10.04 sec 10.9 GBytes 9.29 Gbits/sec receiver  
That's in one 10GigE port and back out the other.  IOW: it's routing and filtering all of that.  10Gbits/sec of data is nothing at all for any modern day consumer-level CPU.  If anyone tells you otherwise, they're trying to sell you something.

Thank you!
 
The ISP are not providing it, they did say they would provide the connections between my kit and their kit, whatever they need. I will double check that they will have the SFP’s to connect.