I think Nocowl should evolve too but that's just me.
And yes Fearow could use an evolution, but it's like a secondary regional bird, just how some regions have two regional bugs (Weedle, and Caterpie, and Wumpel's evolutions) so maybe it won't receive an evolution just like the other two stage birds :(.
Yea the early pokemon of each gen are usually clones of previous ones in terms of data (same amount of stages with similar stats just shuffled around a bit).
So Starly/Pidove are clones of the 3-stage bird concept that Pidgey introduced,
while Hoothoot/Taillow/Wingull are clones of the 2-stage bird concept that Spearow introduced.
Each gen there is at least of of either.
gen 1=one of both - a 'Pidgey' and a 'Spearow',
gen 2=just second - a 'Spearow',
gen 3=two second - two 'Spearows'
gen 4=just first - a 'Pidgey'
gen 5=just first - a 'Pidgey'
and gen 6= at least the fourth 'Pidgey' (Fletchling is seen to have 3 stages in a pokedex screenshot)
These are 2 distinct leagues of birds, and the 2-stage ones are not meant to be compared to the 3-stage ones, and would probably end up stronger than them if they gained new evolutions since they are stronger than the middle stages.