If you are content with 50 crystals then GR fleet will do that for now, but checking your account you are only small distance further from Executor than making Negotiator fleet really viable. Only ships you need to grind for is Razor Crest and Imperial Bomber vs 5 ships for Negotiator. Sure you need to farm more toons to 7* (6 vs 3) for Executor and to relics (10 vs 6) But that should not really be much of a dealbreaker considering income boost coming from it and toons being accelerated. It is big investment to get Piett and Boba to R8 on your account currently, so much of it depend on if you are willing to commit to it and save crystals you get for materials.
To me in your situation going for GR fleet instead of Executor is a huge waste, with moderately higher investment you could have fleet than can carry you to stable 200 or more crystals daily income. But that's just my thought on it. If there are more people outside that top35 in your shard playing the game, they will eventually get Executor, Profundity or Leviathan and you will be out of crystals soon enough anyways.
I am not day 1 player myself, started in January 2017. For a long time there was ~20 people with Executor or Profundity, but in past 6 months we have had quite an increase on those and have now full top50 with Executor or Profundity.
