He's lost a ton of confidence and all but I'd try to get him back on track behind a better line. I'd just add another vet to compete with him (my preference is Minshew but there are other options this offseason) and I'd also draft a developmental type.
Re: the dev draft choice whoever it is has to be a quick processor with good vision and accuracy. Scrappier the better, IMO that type of personality jives well with McVay which is important too.
But I'd keep Goff and try to build his value. Then trade him midseason next year to some desperate (hopefully AFC) team if I feel like he's hit his ceiling or keep him if the line is good and he gets back to his 2018 self.