I don't think you'll have any problem adding those two fish if the tank is all done cycling, and nitrates aren't high. Be careful not to overfeed. Then wait a month before starting to slowly add other fish.
I would go spend about $80 on cleanup critters right away though. In my opinion, a tank that size with a sand bed needs about 2 dozen scarlet hermits, 2 dozen blue leg hermits, a dozen cerith, 20 nassarius snails, and a fighting conch. As you can see I'm not a big believer in snails for cleaning the rocks and glass, but you could also add a handful of astreas if you like. (I think they just get in the way of the cleaning magnet, and fall over upside down and die.)
I think a robust cleanup crew helps check algae outbreaks before they really become a problem, and they avoid buildup of junk, crap, and extra food in the nooks and crannies in your tank. Also, they make the tank a lot more interesting to stare at.