That does look very involved... Anything beady is outside my experience, but there's a couple of bits I can comment on.

You've got square collets for the sapphires; have you tried setting square stones before? If it was me, I'd either source some square tubing, cut it to lengths & solder jump rings on or make up a master & have it cast - assuming you can't find suitable settings. But that all takes time (and yes, soldering with the correct gold solder for the grade of gold!).

Could you, for example, substitute gemstone beads for the settings?