I started with bar box 8 ball, as many a player does who takes up the game upon reaching legal drinking age (in the U.S. at least).I always considered 8-ball the smorgasbord of games. It has a little of everything and requires a little of everything.
Of course, I went through the phase of thinking 8 ball, especially bar box 8 ball, was "too easy" or a banger's game or whatever. But it's actually a GREAT game and highly strategic.
My first night of Double Jeopardy league, I clobbered a 2 in 9 ball and then promptly lost to her 2-0 in 8 ball. Realized how deficient I was in that game and had to go back to the drawing board.