Zeta Mats (Fleet Shipments vs Ability Challenges)

For what it's worth: I'm taking the challenge farming route. I finished TFP (G11 now), put B2 on hold (don't use him in arena anyways & get 1st more often than not) and I'm farming Spy in Cantina. Though not a stellar toon his ship might be viable. I am solely farming Blue prints from GW & FS. Probably a bad move but I am also farming Maul in FS & Shipments. I'm 19 shards away from unlocking Spy & 32 shards away from unlocking Maul. We'll see but I'm hoping unlocked & geared up they are sufficient. My Sun Fac who is 4* does reasonably well. My hope is that having 5 DS ships (instead of the minimum 4) will help offset the weaker pilots. We'll see. I have 100 Spy ship shards & 135 Scimitar. I have yet to see Slave One even once in the FS but save a little currency just incase. (Since I have G10 boba). I would rather a reliable long term solution than what I consider a risky faster solution. Plus once I have the challenge unlocked if I choose I can save for more Zetas. I sit at 11 in ship arena @ 103K power.