Hi Lee and A-M,
Birds which are 'hand-reared' from before their eyes open will imprint socially (and later sexually) onto the 'type' of person that feeds them. As adults, they will want to mate with, and defend the same type of person who fed them as a baby. Obviously, in a the normal 'wild' or parent-reared situation, these behaviours are directed to their own species and, normally (though not always!) to one of the opposite sex. All you are seeing with your bird is the result of this human mal-imprinting. The chances of it occurring can be avoided or at least reduced, by breeders ceasing to use parental deprivation for raising of baby birds.
Re. flight; baby birds have a strong *instinctive* urge to fly, but not the skills of flight. The skills have to be *learnt* by trial and error, and this is best done during the birds' first few months of life as a fledgling. If a baby bird is ever deprived of flight by wing-clipping or over-use of the cage, then it may never fully fly as a normal adult should. Birds have a reflex predator escape response which initiates flight from any fearful stimulus. If this cannot carried out, then yes, the bird may show what is called displaced aggression, caused by the behaviour being frustrated.
The effects of imprinting cannot normally be 'undone', once a bird is no longer a baby; but the worse effects of them can usually be modified with some basic behavioral work.
In addition to these aspects, some birds are more 'fiesty' or 'hot-blooded' than others. Generally, species who are nomadic (most Poicephalus species, Galahs, budgies etc.) are more easliy hyped up and it is best, when interacting with them to adopt a slow, careful approach, using a calm voice at all times. This increases your chances of maintaining stimulus 'control' (where the bird agrees to be compliant with you). My Meyers, Mr Big, behaves in much the same way as your Senegal; given that he was parent-deprived, his behaviour is therefore 'normal'.
Not sure if this helps, but hope it at least explains things a bit.
Google general scientific articles on imprinting for more info on this aspect of birds' and mammals' behaviours.
You wont have a dull moment with most Poicephalus species!