Like others have mentioned, abuse flax based leves all the way to 50. Flax is cheap.
If you feel that you need to do leves that require wool and/or felt based items, my advice is not to do triple turn-in leves. Triple turn-in levequests are the most efficient when it comes to exp per levequest allowance. If you have plenty of levequest allowances and are being hindered by gil, then single turn-in levequests are better, since they maximize exp per item.
I have to agree with you here, I hover at over 90+ levequests and from an items point of view it takes far less to repeatedly do one. Especially since the one offs usually use far less items.
I farm fleece and buy snurble tufts (by the way there are far more camps for fleece than have been quoted - I use one up a mountain with 6 mobs that no-one ever goes to - unless they see the FATE that pops there) but I still think felt and wool are a pain!
Not as much as velveteen mind you - although RMT/bots seem to have eased their monopolising grip there.
My weaver is currently 45 and I'm in no rush to get to 50 on any of my crafts - my main activity is doing GC requests unless I'm near a *5 level (within 2 levels) when I will use levequests to get it there.