When I had 38mb I lost about 3mb using WiFi, but the loss on 76mb is appalling.
it's not losing any more than it was, it's just that wifi is limited in speed. Frankly if you got 35Mb/s on wifi you were doing better than most. Last I checked mine struggled to get much over 20Mb/s which is why I only use it for my phone.
There are two forms of wifi. The older type uses a lower frequency of around 2.4GHz. The more modern uses 5GHz. With the lower frequency version you'll be suffering interference from your neighbours since everyone and their dog uses that frequency block. The higher frequency block is relatively clear but does require that your equipment support that frequency and older/cheaper equipment may not.
But even on 5GHz I think you'll struggle to make best use of your connection. If speed is important to you then a wired connection (Ethernet or PowerLine adaptors) is the only way to go. Wireless will always be a compromise.