Well if they were in the game these enemies would drop half used vigor bottles so there could be a chance of refilling your charges. Yeah I prefer to improvise with something new and unexpected than to do something that you know how to do. Like what if there were unstable evolutions to the vigors like one can be making the electro bolt jump to other enemies and the other evolution would be like a massive electro bolt that deals more damage an stuns longer but to a single enemy. For bucking bronco it could be slamming the levitated people on the ground which knocks hem out for a few seconds or carrying a few enemies away into the clouds (like one or two put of five enemies).
Loot vigors/nostrums (with varying counts of doses and a few empty too) would be logical and that way you (player) might find more varied/random ones (at least once in a while).
The question would be would the opponents (enemies ... do we ever have any allies in this game ????....) all be frequently using all the different nostrums/vigors themselves and thus have to have their scripted behaviors/AI know how to use them properly (static choreographing them could be done but that usually leads to the scene playing the same way every time).
Throw in some 'fake' nostrum/vigors (with odd names) for a little variety -- the era was rife with charlatans selling 'patent medicines' that usually were little more than high octane alcohol and a few unsavory components.