Fishing question

Hey,

I am starting to get into professions and FIshing seemed to be like an easy start. I do have a question though. I just put an Algari Weaverline on my Bismuth Fisherfriend as I thought once I get the Aqirite Fisherfriend I can just put a new Weaverline on it.

Now i got a Seekerthread though, should I save those up, until I get the better Fisherfriend? Also how do you even get the Artisan's Acuity?