Let's just take 3 punches, 3 kicks, and 3 throws to simplify the discussion:
- Jab (straight line), hook (horizontal curve), upper cut (vertical curve).
- front kick (straight line), round house kick (horizontal curve), side kick (straight line)
- leg block (side way rotation), hip throw (forward bending), inner hook (horizontal leg curve),
I would not consider the first 6 as drill practice. This is just practicing 3 different punches and 3 different kicks. The 3 different throwing techniques I don't know much about, but it seems that if it becomes solo practice, these 3 would become more like drills.
Like Piquan is not just one block and one punch. It teach you how do work with your body with vertical movement. This is just like practicing 'hip throw', or 'forward bending'. It will let you practice a basic body method for a whole range of throws, not just one. This is the difference between practicing one single punch (a very limited way of practice) and practicing a "drill" (a basic body method for a lot of variations).
Single punch and single kicking practice should always be made on a surface, a bag or protection. "air-practice" is something more abstract, it teach you different things than the actual punch or kick, which need actual resistance to become a 'true' punch or 'true' kick.