I could see him in the running back mix. Trevone Boykin was bounced around between QB, WR and RB. He was raw and a gunslinger as a QB, but very athletic. He did whatever they asked him to do (TCU). New OC came in this past year with a new playbook and system, and he won the QB job over an Aggie transfer that backed up Manziel. Look how great that turned out. Coaching can make a difference if a player has the tools and applies what he learns. Boykin is really unbelievable and a totally team player. It's been great seeing him grow each year.
As for Armstrong, I really think it depends if the new staff can help him improve, and whether TA will embrace, learn and apply. The new staff knows QB's pretty well apparently, so it will come down to TA. If he can't, then he won't be starting.
DPE played qb in HS, and JT was in the mix as a wildcat until he got injured. A lot of raw, dual threat guys in the rotation the next couple of seasons (not only at Qb, but at Rb, Wr, Ol, those kinda Ol's that also catch. I don't know what they're called but Wiscy and Minn used them a lot). Should be a fun ride if they do develop.