Only one caution about the convicts... I would not keep a pair of them together unless you are set up for breeding facility with another large tank and some sort of outlet scheduled ahead of time for the fry. They breed easily, have up to 100 fry in a spawn, and grow amazingly fast. They are also great parents, so you can expect the fry to survive and leave a 75 gallon way overstocked very quickly. They're dirty and messy, so maintenance can get out of hand quite easily. If you plan to breed them, let us know and we can prep you for that... but again, find an outlet for the fry BEFORE attempting it. Most pet stores won't even take donations of convict cichlids anymore.
Africans would be my first choice... another option would be a silver baracuda. Be careful that the fish isn't mislabeled... they are commonly mismarked in pet stores. I will do some research over the weekend and try to get more details to help you determine proper species ID. With the baracuda, you can still see the teeth, they don't get as large (about 10-12 inches) and can be kept in a 75 gallon long term, especially if only 1 is kept in there. You'll get the same "look" as with the tiger fish, but something more suited to an aquarium.
Hope this helps! I'll be back next wk... will post more for you then.
Have a good weekend.