Hi from a new member!

Hey, was looking for a decent place to ask questions and whatnot about saltwater fish and this seems to be the place!  My boyfriend and I purchased a 29g biocube in December as a Christmas present for each other and have been having fun getting it all started.
Front view:

Bob the clownfish and the three peppermint shrimp:

There's also a 6 line wrasse we named Ralph, and a Emerald Crab we oh so creatively dubbed Green Crab.  I need to stop looking at fish online, it's all so tempting despite how expensive it is ordering online!  I'm excited to get involved with a group of people I can bother with all my (potentially silly and dumb) questions.

 

After reading so many good reviews of Sea of Marvels, we went in to discuss options there and ended up with a Royal Gramma Basslet.  Hopefully he doesn't hide too much once he gets used to the setup, we were warned that they hide a lot but the S.O. thought he looked like the coolest option.  The S.O. also decided we need the nurse sharks one day also.... heh, if only.  I'm thinking I would like to add a goby of some sort, maybe a firefish, and then see how things are settling out.  Eventually I'd love to get an anemone and get more into corals, but I want to make sure we are able to keep this set up in decent shape before investing too much into corals.
Also, quick question, does anyone here have any experience with smaller urchins?  I was eyeballing this and was wondering if there were any opinions on how good/bad it would do in our system.

 

There's a small urchin on liveaquaria (blue tuxedo) that says it's reef safe, but I'm still a bit leery of it since I know most urchins like to chomp on the corals. I like urchins though, so if I can find one that is safe I'd love to try it out. I did keep cichlids (and a giant plecto who would swim to the front of the tank whenever I was around, among others)in college, but I didn't do much on the testing end of things, just water changes and tank cleaning. People always say guppies are boring, but seeing one of my guppies give birth is still one of the coolest things I've seen in the aquariums I've had.