by lines he's saying... for each disc what flight paths are you using it for.
generally speaking (assuming you throw RHBH - right hand back hand)... overstable discs = right to left, stable = straight, understable = left to right
throwing discs on a hyzer generally create right to left lines, anhyzer create right to left lines. there's a lot more depth to this discussion but the more you're on the site the more you'll start to understand the lingo and shot shaping techniques.
generally when people post their bags they include their consistent distances with each disc as well as what they use each disc for.
for instance let's take your wraith... it's an overstable disc (os) which means that for the most part it's going to fade left at the end of its flight. if your wraith is beat to **** or you can torque the hell out of it you can get it to turnover (meaning go right to left).
so for your wraith you would say something like - echo star wraith (weight of your disc) 300' - main driver, use for "x" type of shot.
now to your bag - if you're only throwing 300' some of your discs are to fast for you; you need to get some slower speed discs and work on your form because chucking the big boys down the fairway will not help you improve your game. honestly if you're relatively new, your best option is to take your comet to the course with some other mids and putters and just play with those discs. that will help you improve your form immensely and eventually you'll find that holes you were throwing your fast drivers on... you're now throwing your mids or putters on.
if you don't want to do that i'd at least get the katana out of your bag until you get your distance up. i'd get all but the eagle out for now and possibly pick up a tbird or tl to compliment it if you're in to innova discs for drivers; maybe throw in a leopard for straight tunnel shots as well. if you want to know more about other brands use the search function in the forum to look up specific discs and read the threads about them; it's a great way to learn more about what each disc can do for you.
once you can get your eagle up to around 320' you could bring the wraith and archon back in the fold. the wraith is actually a great distance driver for beginners and it compliments the archon really nicely IMO. at that point you should be able to get both of those discs in at least the 340' range.
all of that aside max distance isn't really all that important despite what some people will tell you. what is important is controlled distance so if you can't control your disc up to certain distances then they are no use to you. work on being able to hit lines consistently with each disc as well as learning to work in new lines; experimentation is fun and a great way to improve your overall game.
to work on your form look up some drills you can do to help. here's a couple to start with.
http://www.youtube.com/watch?v=nED7gcXobEo
https://www.dgcoursereview.com/dgr/forums/viewtopic.php?f=2&t=19220