Granted weapon skills

... feel a little disadvantaged compared to any other skill you can just socket.
1) You can't add sockets with jeweller orbs, so the sockets you have are dependent on the skill level the weapon grants. This means it's VERY hard to find a good/decent weapon since you also have to look at skill level the weapon grants. Getting a 6 link is almost impossible. A level 19 skill is a 5 link, I assume 6 link is locked behind a level 20 weapon skill (currently there is no level 20 weapon on trade with the skill I want to play).
2) You can't add quality to that skills although the granted skill shows additional effects from quality.
3) Prism of Belief (Diamond) grants skill levels to (almost?) every socketable skill but not for granted weapon skills.