welcome to the world of wakeboarding and wakeworld respectively.
All over the world you can find some really cool peeps to ride with. never been to austrailia, but i have rode with a few people from abouts there visiting the states. Sounds like you have a few friends you are riding with already and that is fantastic.
You might want to think about your interest in hitting rails or even going to a cable park, there is one about 1 hour from you that i googled http://www.cableski.com.au/
but then again if you got boat ramp only 15 min away then cable riding might not have the same appeal.
Anyway. it is nice to have a board that has a durable base and durable sidewalls for hitting rails and cable parks if you ever decide to.
All of the boards you mentioned are good boards. the LF Trip and CWB faction are the only boards you named that have a continuous rocker. These boards should ride a bit faster and the pop will be less aggressive (not to say it wont pop you as high). The other boards as well as your Omega have a three stage rocker of some kind that gives the board a bit of a buck at the wake. If you want more speed and a bit less abrupt style of pop then make the switch to continuous rocker, otherwise stay with the 3 stage boards and hybrid rockers. If there is a LF watson wakeboard (three stage style) at your store you might want to include it in your list. the watson and witness are two very popular boards in the LF line.
Does your store sell anything other than CWB and LF if you want more suggestions?
Don't underestimate a good pair of boots and a good wakeboard rope with handle. boots connect you to your deck and the rope is your life-line to your riding experience
try on a few pairs of boots in the store. lean and bend in them to feel them out. hop up and down to feel the footbeds
anything that says it is made of spectra and or dyneema! these ropes will not stretch and will give you user friendly line tension and POWER
find a handle that feels nice. maybe put a bit of pull on the handle (with help of a friend or looping the rope on something) to make sure it feels good with tension