Exactly there is no diversification based on mandates of each unit
This is exactly why the expansion of Paras starting in 1978 and then Blowing up in 2003 was extremely retarted.
See, it used to be like this:
9 Para- Mountain specialists
10 Para desert specialists
21 Para- NE specialists. (1 para was turned to SF before 21 Para SF for absolutely no reason whatsoever).
Then expanding 2 Para and 3 Para in 2003 was semi justifiable, but then again, completely failed to modernize. Although 3 Para has a excellent record as an SF unit.