What's a Good Skateboard Longboard for a Beginner?

Well, i first began with a sector 9 ala moana which dont get me wrong is INSANE for cruising/carving but now as i progress in becoming a lonboarder, i want a board with more flex (bounciness) and more controlled carving. With your specifications, i would go with a sector 9 aperture longboard which is 200 dollars retailed (150 online in some places) This board is wonderful for carving and cruising around and can probably handle speeds up to 20 mph with loose trucks and maybe 25-30 if you tighten them up and learn how to ride with stability. Also, look at some original longboards if you are just starting The pintail 37, and torpedo 40 both seem to fit your specifications and are great to learn how to ride on. I would get s8 or s10 trucks on them, orangatang or abec 11 retro zigzags on them which would total about 210 dollars. Hope i helped :)