Just got new toyo proxes 4s and my steering wheel vibrates at high speeds (70+). Is this just because the tires are new or could it be a bad balance job? I checked the air pressure and also got an alignment already.

Bad balance job. Go back.

Tell them to use the spring and cone from BEHIND the wheel. I have balanced many WRX rims and they seem to come out much better that way. Normally they just use the cone from the front of the wheel and it can sit on the hub funny. You should always re-check your lug nuts, also.