"Here in st. louis I've never caught a bass over 5 lbs so buying a 7-8 wt right now, with just starting out an all seems kind of pointless to me. I wont be hurling anything too huge, maybe some decent size streamers and some poppers on the mineral fork and simaler waters."
First of all there are several components to picking that fly rod.
The quarry for instance. A Bass has very hard lips when compared to a trout, hence the phrase, "rip their lips off," applies when hook setting. That lends itself to a stiffer or heavier weight rod, and puts you into the six to seven weight rod.
Second, the flies are bigger with Bass flies ranging from about a size 10 up to a two ought. There again you are in that seven weight rod.
Third, you'll find that poppers and deer hair flies (a favorite) are air resistant and again a bigger rod is needed to get the out "nicely."
Last of all if you should fish the salt, or bigger fresh waters the wind is a factor and wind dictates some rod power. In short get a seven if you want it to happen "nicely,"but if budget or other constraints get in the way use what you have but be prepared for a bit of slop and frustration.
As far as getting a Bass line goes, it will likely be designed for warmwaters and therefore not so kinky as the trout offerings.
" Was wondering if just buying an extra spool and using some bass taper line and possibly over lining would help cast larger flies? Whats the difference between my rio gold and a bass taper line? Also I take an annual trip to sanibel island every summer and wanted to do some fly fishing for maybe some lady fish, would over lining help throw some streamers to them? Again I want to use what Ive already got, not buy a whole new set up. Any advise will greatly help since I'm still new to the sport. Thanks! "
It would help but not the greatest. On the Rio Gold versus a Bass taper - kinkiness for one and the bass taper is designed to help carry bigger, wind resistant bugs out to the fish.