Have a look at my 3ft tank in fishy showroom. Easy to look after, always busy, no agro and I find it very relaxing. Best part is if you spend $50 on fish, makes a huge difference to tank. $50 on cichlids wont get you many fish. Plus you will probably buy small cichlids which you have to wait for them to colour up. As fish get older and more territorial, it gets harder to add fish. I breed catfish which keeps it interesting for me as well.
Most important thing to remember is, it's your tank, do what you want and enjoy it.