Hi... I know you are excited but I think you need to do a bit more research before you stock your tank. I don't know your level of experience in fishkeeping so forgive me if I assume your are towards the beginner end rather than an experienced fishkeeper..
If you are thinking blue rams, IME they are fairly sensitive/delicate to water parameters and they like high temps that the neons will probably not thrive in.. Yes I know some folks keep them in higher temps but they really thrive in lower temps than the blue rams need.. Bolivian rams will do better at the same temps as the neons and are a much hardier fish.. I agree that the red tail shark, while pretty, can get very aggressive as it grows and may not be the best choice long term.. Take a look at the cories here or on a site like planet catfish or such.. They are very entertaining in a group in your size tank.. I think that the neons, bolivians and cories would make for an entertaining tank.. you should also look at bristlenoses if you are thinking of algae eater type fish.. they stay fairly small and will not bother your other fish.. Good luck with the tank and let us know what you come up with.. There are lots of wonderful fish out there for you both to choose from.. HTH Sue