Do you think Locksley falls into this category? I think that determines how many you take in the next couple of years.
Regarding how many QB's to take, here's my thoughts on that. Talking about scholarship only, I think ideally you would have 4 non-true freshman QB's and 3 at an absolute minimum. Counting Merrick as a true freshman in 2016, we have 3 QB's in 2016 and finally hit 4 in 2017. And that's assuming that Locksley stays at QB. If Locksley develops as a QB, then you only need to take one in 2017. But if he's iffy, then you take two.
2014 - One (Swoopes)
2015 - Two (Swoopes, Heard)
2016 - Three (Swoopes, Heard, Locksley)
2017 - Four (Heard, Locksley, Merrick, Buechele)