WELCOME TO AA!!!
Theatrus made some great points. If you can eventually get about 1.5-2LBs of LR
per gallon, you can probably just remove the media, bio balls/wheel from the filter and use it for carbon and extra water movement. I would say go with the filter, learn how the tank works and once you are comfortable with maint. on your tank, you could go filterless or medialess.
Im also waiting to get a protein skimmer until the tank is cycled, is that ok or do i need one now?
I have a FOWLR
and don't use a skimmer. It is recommended by many, I don't really have a place to put one, so I decided not to worry about it.
Inverts....depends on what critters you want to put in there. I have found 4 hermits, and about 30 snails in my 55G. That is a little low, but I am waiting on a few other critters (like a conch) to place an order for more of a clean up crew. I like urchins. If I had my choice, I would get a long spined urchin or Blue Tuxedo Pincushion.
you could even go with a sand sifting goby, like these:
I think it is really a preference. It seems it is better to have fewer than more....