tall tanks aren't great for most SA cichlids, but you could do angelfish . . . maybe a planted tank with smaller cichlids (Rams, laetacara) on the lower levels and schooling fish for the upper levels . . .
Angelfish are a much better choice than discus. Discus are wider in body diameter than angels. If you opt to try angels, then you could also add the smaller cichlids such as rams or apistogrammas there. Let us know what your final plan is.