I think you are...
Vontaze Burfict, the Cincinnati Bengal player whose on-field antics caused his team to lose the AFC wild card game in the 2015 NFL playoffs.
I am far from perfect
Burfict is known for causing issues on the field. In addition, though he was considered a very good draft choice, his on- and off- field antics in college and poor performance at the combine, marked him lower in the eyes of teams, and he went undrafted.
Though perfect is like me
last names rhymes with perfect
I acted like an idiot
Happens almost every year. He inevitably causes a fine-worthy penalty sometime during the season.
On live late night TV
The Pittsburgh - Cincinatti playoff occurred at night on January 9th, 2016.
You could say I am a cat
With stripes of orange and black
Cincinnati Bengals, named after Paul Brown's high school team
But I am more an angry bull
See above concerning on- and off- field antics
For flags make me attack
Seeing a yellow flag on the field seems to make him angrier and cause more issues on the field.
My first you've never heard before
Vontaze is not really a common first name, at least in the U.S.
My last is also rare
Burfict is also not a really common surname either.
But it's the part that's perfect
(almost, not everywhere)
Again, last name rhymes with perfect.
Of course, this could also apply to
Adam Jones (aka Pac-man), Burfict's teammate who caused an additional penalty after the Burfict penalty for pushing a ref on the field.